De Quervain s syndrome: It may not be an isolated pathology

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1 Original Article De Quervain s syndrome: It may not be an isolated pathology Hand Therapy 2016, Vol. 21(1) 25 32! The British Association of Hand Therapists Ltd 2015 Reprints and permissions: sagepub.co.uk/journalspermissions.nav DOI: / hth.sagepub.com Karen Redvers-Chubb MCSP; MScErg Abstract Introduction: This paper details a retrospective review of patients records diagnosed with de Quervain s syndrome following a traumatic event but no history of repetitive strain. Methods: Data analysis of 41 patients was performed. The inclusion criteria were pain over first dorsal compartment, pain on resisted extensor pollicis brevis and/or abductor pollicis longus, and a positive Finkelstein s test. The assessment included a subjective history to establish a repetitive activity or a traumatic incident and diagnostic tests to establish possible instability or osteoarthritis. Results: There were 13 men and 28 women with an age range from 20 to 72 years. Statistical analysis was undertaken using Fisher s Exact tests. 46.3% (n ¼ 19) of 41 patients had a ligament injury diagnosed after the de Quervain s. 94.7% (n ¼ 18) of 19 patients with ligament instability had a history of trauma, and this was statistically significant. Clinically significant was that 82.9% (n ¼ 34) of 41 patients demonstrated extensor carpi ulnaris (ECU) muscle weakness, but there was no statistical significant correlation between ECU weakness and ligament instability. Patients could have ECU weakness without ligament instability; however, patients with ligament instability appeared more likely to have ECU weakness. Conclusions: The results would suggest that de Quervain s syndrome, in a proportion of patients, could be secondary to underlying wrist pathology due to previous trauma. If the patient does not report a true repetitive strain history, a more thorough assessment may need to be undertaken to establish if there is any underlying pathology. Keywords de Quervain s, trauma, extensor carpi ulnaris, ligament instability, repetitive strain Date received: 18 February 2015; accepted: 17 July 2015 Introduction De Quervain s Syndrome has been defined as a condition that originates if abductor pollicis longus (APL) and extensor pollicis brevis (EPB), in the first dorsal compartment (a tight osteoligamentous tunnel) become inflamed through friction of the two tendons gliding in the tunnel and leading to the patient experiencing pain. 1 Blood flow and nutrition become compromised and adhesions develop causing the tendons to undergo stenosis (narrowing) Pensak et al. in 2013 published a paper which highlighted research suggesting that de Quervain s might be a myxoid degeneration, 1 the definition of which is given as: a degenerative process in which the connective tissues are replaced by a gelatinous or mucoid substance. 4 De Quervain s syndrome is often referred to by different terminologies: tendinosis (degeneration of the tendon with no inflammation), 1 tendinopathy (injury to the tendon itself), and tendovaginitis/tenosynovitis (inflammation/thickening of the fibrous wall of the sheath). 5 In this paper it will be referred to as de Quervain s syndrome a group of symptoms characteristic of a condition. 6 There has been little change in the understanding of the pathophysiology or management of de Quervain s since its discovery in 1895 when Fritz de Quervain described pain over the first dorsal compartment as a tenosynovitis, following repetitive activity. Another eminent surgeon, Theodor Kocher, also described de Quervain s as a fibrous tendovaginitis 2,5,7 around Burns & Plastics Outpatient Department, Wythenshawe Hospital, Manchester, UK Corresponding author: Karen Redvers-Chubb, c/o Hand Therapy, Burns & Plastics Outpatient Department, Wythenshawe Hospital, Southmoor Road, Manchester M23 9LT, UK. Karen.RedversChubb@uhsm.nhs.uk

2 26 Hand Therapy 21(1) the same time; however, it was noted clinically that there was no history of the repetitive strain characteristic of de Quervain s with his patients. The theory that repetitive activity causes de Quervain s syndrome, often leads to it being referred to as a repetitive strain injury or overuse tendinopathy. 8 When carrying out the activity in question, the typical posture of the thumb is usually one of abduction, with the wrist in ulnar deviation, whilst gripping an object, e.g. hammering. 9 There are two factors which could predispose patients to develop de Quervain s syndrome. One factor may be the position of the wrist when functional activities are carried out. The wrist is usually in an extended position which increases the angulations of APL and EPB at the extensor retinaculum. This may increase tendon friction within the tight tunnel, which could be further escalated by the carrying angle at the elbow. If the angle at the elbow is more acute, it could amplify the tendon angulations at the wrist producing greater friction. 7 Demographic studies indicate women are more likely to develop de Quervain s syndrome, 3,10 and this could be due to the greater carrying angle at the elbow for females. On average, in men the elbow angle is approximately 11.6 and in women Secondly, there are anatomical variations. Some patients have an anomalous presence of more than one osteoligamentous tunnel, which expands the frictional surface area potentially leading to de Quervain s syndrome. 1,13,14 Hunter et al., 3 reported that fewer than 20% of people may have what is classed as normal anatomy, that being the presence of one tunnel. The symptoms associated with de Quervain s include pain over the first dorsal compartment at the wrist which may radiate proximally or distally, pain on APL EPB activity, reduced grip strength and the patient may report dropping objects. 2,3,8,12,14 Therapeutic treatment is usually based around that of an inflammatory condition and can consist of rest, ice, splinting, ultrasound, exercise and injection therapy, despite there being evidence that most tendinopathies are not primarily inflammatory in nature. 2,7 Successful treatment prevails in the majority of patients; however, those with unresolved symptoms present an on-going challenge for both surgeons and therapists. This retrospective case review was instigated when patients with a diagnosis of de Quervain s, referred to the hand therapy unit at the University Hospital of South Manchester, demonstrated an atypical history for this condition. In a proportion of the patients, it was noted that there was no history of repetitive strain characteristically associated with de Quervain s. 6,8,12 These patients often reported a traumatic event preceding the development of de Quervain s, which may have taken place a number of years previously. Conventional treatment, both conservative and surgical had failed to resolve symptoms, or symptoms had recurred. These observations prompted a retrospective case review to investigate the question: Is de Quervain s syndrome always an isolated pathology or could it be secondary to a concomitant underlying wrist condition? Methods A review of 48 patients case notes, with a diagnosis of de Quervain s syndrome, referred to our service over a 5-year period from 2009 to 2013 was undertaken. The referrals were all hospital based from plastic or orthopaedic surgery consultants. There was missing data from medical or therapy notes in seven patients, which could not be recovered. These patients were therefore excluded from the final data analysis. This left 41 patients notes which underwent analysis. Information was gathered from medical and therapy records on patients over the age of 18 years referred to the hand unit with a diagnosis of de Quervain s, who had the following symptoms: pain over the first dorsal compartment, pain when EPB and/or APL were tested and a positive Finkelstein s test. Therapy assessment Two senior hand therapists in the unit with 12 or more years of experience in the management of hand and wrist injuries carried out the initial assessment. This followed a standardised format for patients with hand/carpal problems. The assessment included a subjective history to establish whether there was a history of repetitive activity or trauma preceding the development of de Quervain s. As per our unit s working practice, all patients had range of movement and grip strength assessed. The range of motion at the wrist was assessed using a long arm Baseline goniometer. A Rolyan Sammons Preston Jamar dynamometer was used to assess grip strength. 14,15 The movement and grip strength data were not included in analysis for this case review. Objective assessment also included forearm muscle strength using the Medical Research Council scale(mrc scale), this is also known as the Oxford scale. 16 Hand therapists in our unit are all trained to carry out manual muscle tests using isometric muscle contraction. In order to differentiate subtle changes in strength, the therapists use the plus (þ) or minus ( ) signs. If the strength was assessed as falling between grades, i.e. 3 4, then the therapist noted it as reaching a grade of 3þ. The MRC and a modified MRC scale are used to assess muscle power. Paternostro-Sluga et al. 16 published a paper in 2008 which demonstrated the reliability of MRC and the modified MRC. The MRC and modified MRC

3 Redvers-Chubb 27 demonstrated a reliability of between 0.61 and 0.8 with Spearman s correlation coefficients suggesting substantial agreement for inter-reliability and 0.8 for intrareliability. The Finkelstein s test was used to diagnose de Quervain s syndrome. The test involved the patient grasping their thumb into the palm and the therapist abruptly ulnar deviating the hand. 15 It was positive if pain was elicited over the first dorsal compartment. This test is carried out by medical practitioners to diagnose de Quervain s, despite it potentially eliciting false positive results due to strain on the radial collateral ligaments of the wrist, the scaphotrapezial ligament and first carpometacarpal ligament (CMCJ). 17 This test has also not been extensively evaluated as a provocative test to aid diagnosis of de Quervain s syndrome. 8,18 Despite the limitations, it is a test still widely used by the medical profession. Other specific wrist/thumb tests were used to differentially diagnose ligament or joint problems, for example the Watson s shift test for scapholunate interosseous ligament (SLIL) injury, the grind test for diagnosing osteoarthritis (OA) of the first carpometacarpal joint or the triangular fibrocartilaginous complex (TFCC) provocative tests. Any scans or other investigative tests were also reviewed, which included X-rays, MRIs or CT scans. Ongoing treatment was carried out by a hand therapist in the unit in accordance with the assessment findings. Conventional treatment as previously described for de Quervain s syndrome was given if the patient was diagnosed with an acute episode of de Quervain s syndrome; however, any underlying pathology simultaneously diagnosed was also treated, for example ligament instability. Data collection The data collected for analysis included gender and age range to determine if our group of patients followed the demographics of other studies. 3,7 Information on the history preceding the de Quervain s syndrome and whether there was a traumatic incident or repetitive activity was collected and any treatment the patient had received for the de Quervain s, prior to their referral into the unit. If they had undergone treatment, data was collected on the outcome. The results from any investigative procedures such as X-rays or scans was documented and analysed. Forearm muscle strength, as well as the eventual outcome after assessment and treatment by the hand therapist was also evaluated. Data analysis The data on 41 patients underwent statistical analysis. This was carried out by the University Hospital of South Manchester medical statistics department. Categorical parameters were summarised using frequencies, percentages and cross tabulations and analysed using Fisher s exact tests. Due to multiple comparisons, the critical values were adjusted for number of comparisons using Quasi-Bonferroni correction, applying a critical value of (0.05/4) as significance level. Due to the small numbers of patients in certain categories, only large differences were significant. All summaries and analyses were produced using SPSS version 20. Results Of the 41 patients, 68.3% (n ¼ 28) were females and 31.7% (n ¼ 13) were males. The 41 patients age ranges were divided into two groups: years and years. The subdivision was carried out within these parameters to take into account the discrepancy within the literature, as to which age group is most likely to develop de Quervain s. Some literature states the age range as years, 3 whilst other papers report it as years. 6 The age range subdivision for this review meant that only seven patients were in the age group 50 55, the range in dispute in literature. The females in this review were almost equally divided across both age groups: 57% (n ¼ 16) were aged years and 43% (n ¼ 12) aged 51 72; however, 92.3% (n ¼ 12) of males were in the younger age group, years. The gender ratio, female to male, was approximately 3:1. Again, the literature highlights discrepancies. In some papers, it is 4:1 3 and in others 6:1. 5 Overall, the demographics of the patient in this review were consistent with other studies. 3,7,10 Assessment history A finding in this review, which could be of clinical importance, was that 73.2% (n ¼ 30) of 41 patients reported a traumatic incident to the wrist or hand preceding the development of de Quervain s syndrome. The development of de Quervain s usually occurred within the first year following trauma to their wrist or hand. The majority of trauma involved hyper-extension of the wrist joint, for example a fall onto the out stretched hand (FOOSH): 43.3% (n ¼ 13) out of the 30 patients had a FOOSH. Other trauma included fractured wrists, hyper-flexion injuries and gripping or twisting incidents. Of the 41 patients, 24.4% (n ¼ 10) presented with a repetitive strain history. This history is consistent with de Quervain s syndrome and they reported no history of trauma. There was one anomaly that did not fall into either category of trauma or repetitive strain.

4 28 Hand Therapy 21(1) Forearm muscle strength Another finding which could be of clinical importance was that the extensor carpi ulnaris (ECU) muscle transpired to be the weakest out of all forearm muscles (Figure 1). A muscle was defined as weak if it was assessed as below a grade 4þ, when compared to the contralateral side, taking into account dominant and non-dominant sides. Out of 41 patients, 82.9% (n ¼ 34) had ECU weakness. Both men and women had ECU muscle weakness across all age ranges, irrespective of whether they had sustained trauma or not. ECU weakness and ligament instability were analysed for correlation, but this demonstrated no statistical significance. There were 52.6% (n ¼ 18) patients who had both ECU weakness and ligament injury; 47.1% % of Patients Muscle Weakness & Gender ECU ECRL ECRB FCR FCU Muscles Female Male Figure 1. Percentage of patients with Grade 4þ strength and below in forearm muscles, according to gender on initial assessment using the Medical Research Council Scale (MRC). ECU ¼ extensor carpi ulnaris, ECRL ¼ extensor carpi radialis longus, ECRB ¼ extensor carpi radialis brevis, FCR ¼ flexor carpi radialis, FCU ¼ flexor carpi ulnaris muscles. (n ¼ 16) patients had ECU weakness with no ligament instability. Of those with ECU weakness (n ¼ 34), 38.2% (n ¼ 13) patients required surgery. The type of surgery undertaken included the following: 17.6% (n ¼ 6) who had ligament stabilisation procedures, for example: Eaton Littler for beak ligament injury and midcarpal stabilisation and 8.8% (n ¼ 3) required de Quervain s release. The other four had ulna shortening, radial styloidectomy, four corner fusion and carpal tunnel release (Figure 2). The numbers were not statistically significant but potentially warrant further investigation. Gender, age and trauma When gender and age were analysed, it was discovered that 12 out of the 13 males were in the younger age group and of these 10 reported a history of trauma preceding the de Quervain s development. Females were fairly evenly spread across both age groups and the percentage of patients reporting a history of trauma across gender was relatively equal (males 76.9%; females 71.4%). Trauma and ligament instability There were 46.3% (n ¼ 19) of patients out of 41 who demonstrated ligament instability after their referral for de Quervain s syndrome. The statistically significant finding within this case review (p 0.005) (Table 1, Figure 3) was that from this group of 19 patients, 94.7% (n ¼ 18) had had a traumatic event between 1 and 3 years previously. Of the 19 patients demonstrating ligament instability, 52.6% (n ¼ 10) underwent Outcome from the Hand Unit % of Patients No Surgery Ligament Stabilisation Surgery DeQuervains Release Surgery Bone Surgery e.g Ulna shortening Carpal Tunnel Release Figure 2. Outcome for 41 patients following treatment in the hand unit.

5 Redvers-Chubb 29 surgery of whom 60% (n ¼ 6) required ligament stabilisation. Specific ligamentous tissues assessed to be problematic in the 19 patients, but not always requiring surgery included the scapholunate interosseous ligament (n ¼ 13) and the triangular fibrocartilaginous complex (n ¼ 5). Other structures included the beak ligament at the base of the first carpometacarpal joint, ulnar collateral ligament of the metacarpophalangeal joint of the thumb, the lunotriquetral interosseous ligament and the midcarpal joint ligaments. Some of the patients were diagnosed with multiple ligament problems, for example the triangular fibrocartilaginous complex (TFCC) and scapholunate interosseous ligament (SLIL); SLIL and the beak ligament. A proportion of this group of 19 patients, 47.4% (n ¼ 9) responded to conservative management of the ligament instability. Previous treatments There were only eight patients who had not received any treatment before their referral into our hand unit. The majority of patients had received treatment prior to their referral, 80.5% (n ¼ 33) had undergone multiple treatment interventions. There were 28 patients who had undergone therapeutic treatments including immobilisation using a cast or splint and/or hand therapy. Therapy interventions included passive stretches, cross frictions of the tendons, strengthening and ultrasound. There were 18 patients who received a steroid injection and eight had undergone de Quervain s release surgery. Diagnostic tests The majority of patients 90.2% (n ¼ 37) had wrist X-rays. The remaining three patients who did not have an X-ray had received an ultrasound scan only. There were 53.6% (n ¼ 22) of patients who had a MRI scan of whom 3 were diagnosed with de Quervain s; 34.1% (n ¼ 14) had an ultrasound scan of whom 5 were diagnosed with de Quervain s; one patient had a CT scan and one person had no diagnostic tests. Table 1. Proportion of patients with history of trauma and ligament instability diagnosed after the development of de Quervain s syndrome. Ligament instability Yes (n ¼ 19) No (n ¼ 22) p-value Trauma Yes 18 (94.7%) 12 (54.5%) No 1 (5.3%) 10 (45.5%) Outcome from hand therapy. Treatment carried out by the hand therapists included therapeutic management for tendinopathies as mentioned earlier. Those patients diagnosed with ligament instability commenced conservative treatment of the instability to try to negate the need for surgery. Out of the 41 patients, 61% (n ¼ 25) of patients recovered with therapeutic intervention, one patient was still undergoing hand therapy treatment at the time data was analysed, but is unlikely to require surgery and 39% (n ¼ 15) required surgery (Figure 2). Numbers of Patients History of Repetitive Strain v Trauma & Ligament Instability REPETITIVE STRAIN History TRAUMA LIGAMENT INSTABILITY YES LIGAMENT INSTABILITY NO Figure 3. The number of patients with a history of repetitive strain or trauma with a ligament injury diagnosed after referral for de Quervain s syndrome.

6 30 Hand Therapy 21(1) Discussion The results of this retrospective review appear to support the idea that de Quervain s is not always an isolated pathology and could be secondary to a concomitant underlying wrist condition. There are two areas that therapists may wish to consider when assessing patients referred with a diagnosis of de Quervain s syndrome. First, has the patient sustained a traumatic event preceding the development of de Quervain s? In the subjective history section of the assessment, the therapist may want to question the patient as to when the tendinopathy problem started. If the history is not one of a repetitive nature, the therapist could question the patient further as to a possible past traumatic incident which may have occurred. The trauma may have happened several years prior to the development of the de Quervain s. The second area to consider and assess is how effectively the ECU muscle is functioning. Trauma and de Quervain s De Quervain s may develop after trauma due to either a ligament sprain/tear and/or forearm muscle weakness, especially the ECU muscle. It is important therefore to find out if the patient has had a traumatic event preceding the de Quervain s Syndrome. There was statistically significant correlation between a history of trauma and ligament instability diagnosed after the de Quervain s diagnosis and also of clinical importance, muscle weakness primarily affecting the ECU. Knowledge of the mechanism of injury can indicate to the therapist the specific tests necessary to help diagnose any underlying pathology, for example Watson s shift test; TFCC shear test. These tests would not usually be part of the routine assessment carried out for a de Quervain s referral. 20,21 These tests may highlight which ligaments or muscles could be affected 20,22,23 thereby guiding treatment and indicating if further investigations are warranted, e.g. MRI arthrogram. Witchell et al. 19 and Risberg et al. 24 demonstrated that gaining range of movement and strength alone during rehabilitation, did not necessarily equate to a return of full function. They reported that the neuromuscular pathway of joint control via the ligament should be addressed in rehabilitation to achieve joint integrity and stability. Recent papers on wrist biomechanics and what happens in the event of ligament incompetency highlight that Risberg s and Witchell s findings on neuromuscular control may need to be applied to wrist rehabilitation. Joints require anticipatory control of muscles, through competent ligaments, to stabilise joints via proprioceptive feedback. 25,29 It may be that rehabilitation of the wrist should include proprioceptive techniques in order to reduce the risk that ligament and/or muscular incompetency could lead to the development of de Quervain s syndrome. It may develop because of ligament or muscular imbalance. The challenge for therapists is that routine assessment methods and the specific tests for underlying pathologies will not necessarily highlight neuromuscular imbalance. 23,30 Muscle imbalance and de Quervain s Abductor pollicis longus (APL) and extensor pollicis brevis (EPB) are the tendons involved in de Quervain s syndrome. Johanson et al and van Oudenaarde 31,32 describe how alongside APL and EPB, ECU works as a collateral wrist stabiliser. The ECU counterbalances thumb abduction during the release phase of activities, such as hammering, 8 as well as assisting transmission of forces from the forearm muscles into the hand to function. Also, when the forearm is in the neutral rotated position (the position adopted during most loading tasks), the radius and ulna divergence is at its maximum, the ligaments are lax and the forearm muscles are required for stability. 33,34 If ECU strength is inadequate, there will be imbalance of muscle activity across the wrist joint. APL and EPB will continue to work optimally, or may indeed work harder during loading or repetitive tasks, to assist stability and function potentially leading to de Quervain s development. ECU also has a role to play in stabilisation of the ulna side of the wrist during functional tasks via the TFCC. 25 A number of papers describe how the ECU contributes to ulna side wrist stability 27,28,33,34 and how if ECU activity is reduced, it can lead to distal radioulnar joint instability. As ECU functions alongside APL and EPB to assist wrist stability, if the ECU is inadequate it may cause APL and EPB again to work unopposed, which could lead to de Quervain s. 14,23 Furthermore, APL is one of the tendons that contribute to dynamic wrist stability through the dart throwing motion. The dart throwing motion pattern used in all functional tasks is also partly guided by ECU 17,28 through its action on the triquetralhamatecapitate joint. The triquetralhamatecapitate joint is stabilised by ECU preventing the capitate from rotating. 27 The movement pattern is controlled through proprioceptive feedback (this controls velocity and movement) and feed-forward reflexes (this is the anticipatory control of muscles). 30,31 It may be that muscle weakness affecting ECU and/or APL leads to reduction in proprioception and loss of structural or sensory integrity. EPL and/or APL could overcompensate with de Quervain s syndrome as a result. This is a retrospective study and retrospective studies have several limitations. The main areas are selection bias, misinformation or misclassification bias. In this review, the relatively small number of case notes may

7 Redvers-Chubb 31 have impacted on the findings. Retrospective studies often require large numbers for rare outcomes. There may also have been potential bias by the therapists. The same therapist who carried out the initial assessment may also have continued with that patient s treatment and final assessment at the time of discharge. There is ongoing data collection on patients referred with the diagnosis of de Quervain s syndrome to the unit to increase the numbers for a future case review. Conclusion The results of this review into whether de Quervain s syndrome is an isolated pathology or could be secondary to an underlying pathology would appear to indicate a comprehensive and not merely routine assessment may need to be undertaken, to confirm that there is no underlying pathology leading to the de Quervain s syndrome. De Quervain s syndrome is usually treated as a repetitive strain condition. An assessment may need to be carried out which highlights whether there could be a muscular or ligamentous pathology causing APL and EPB to overcompensate. The practitioner should take note of any history of previous trauma (this may necessitate going back several years to before they started with de Quervain s if they have a long history of the syndrome) to the upper limb which could be the reason the imbalance developed. Recent advances in research on wrist biomechanics 10,35 and the impact of instability need to be considered when assessing and treating de Quervain s syndrome. By addressing any underlying pathology it will enable complete effective treatment of patients with de Quervain s syndrome. This may lead to a reduction in recurrence of the tendinopathy. Acknowledgement The author would like to thank Alison Roe (MCSP) for her support and help reviewing this article. She would also like to extend her thanks to Sigrid Whiteside (UHSM Medical Statistics) for her assistance with statistical analysis of the data. Funding The author received no financial support for the research, authorship, and/or publication of this article. Conflict of interest This paper received no specific funding from either public, commercial or not-for-profit sectors. References 1. Pensak MJ, Bayron J and Moriatis J. Current Treatment of de Quervain Tendinopathy. J Hand Surg 2013; 38A: Hunter JM, Mackin EJ and Callahan AD. Rehabilitation of the hand: surgery and therapy, 4th ed. St Louis, MI: Mosby, 1995, pp Hunter JM, Mackin EJ and Callahan AD. Rehabilitation of the hand: surgery and therapy. 5th ed. St Louis, MI: Mosby, 2002, pp Myxoid degeneration-biology-online Dictionary, www. biology-online.org/dictionary/myxoid_degeneration (accessed 3 July 2014). 5. Ahuja NK, Chung KC and Fritz de Quervain MD. Stenosing Tendovaginitis at the radial styloid process. J Hand Surg 2004; 29: De Quervain s Syndrome, patients/commonhandconditions/dequervainssyndrome (accessed 4 June 2014). 7. Green DP, Hotchkiss RN, Pederson WC, et al. Green s operative hand surgery. 5th ed. Philadelphia, USA: Churchill Livingstone, 2005, pp Batterson R, Hammond A, Burke F, et al. The de Quervain s screening tool: validity and reliability of a measure to support clinical diagnosis and management. Musculoskeletal Care 2008; 6: Leventhal EL, Moore DC, Akelman E, et al. Carpal and forearm kinematics during a simulated hammering task. J Hand Surg 2010; 35A: McAuliffe JA. Tendon disorders of the hand and wrist. J Hand Surg 2010; 35A: Van Roy P, Baryens JP, Fauvart D, et al. Arthro-kinematics of the elbow: study of the carrying angle. Ergonomics 2005; 48: Stanley BG and Tribuzi SM. Concepts in hand rehabilitation. Philadelphia: F.A. Davis Company, 1992, pp Kay NRM. De Quervain s Disease: Changing pathology or changing perception? J Hand Surg (Br) 2000; 25: Jepsen JR, Laursen LH, Larsen AI, et al. Manual strength testing in 14 upper limb muscles. A study of inter-reliability. Acta Orthop Scand 2004; 75: Bohannon RW. Manual muscle testing: does it meet the standards of an adequate screening test? Clinical Rehabilitat 2005; 19: Paternostro-Sluga T, Grim-Stieger M, Posch M, et al. Reliability and Validity of the Medical Research Council (MRC) scale and a modified scale for testing muscle strength in patients with radial palsy. J Rehabilitat Med 2008; 40: Moritomo H, Apergis EP, Herzberg G, et al International Federation of Societies for Surgery of the Hand Report of Wrist Biomechanics Committee: biomechanics of the so-called dart throwing motion of the wrist. J Hand Surg 2007; 32A: Valdes K and LaStayo P. The value of provocative tests for the wrist and elbow: a literature review. J Hand Therapy 2013; 26: Witchells JB, Waddington G, Adams R, et al. Chronic ankle instability affects learning rate during repeated proprioception testing. Phys Ther Sport 2014; 15: Huisstede BM, van Middelkoop M, Randsdorp MS, et al. Effectiveness of interventions of specific complaints

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