UNFAVORABLE RESULTS AND degenerative arthritis. Arthroscopically Guided Osteotomy for Management of Intra-Articular Distal Radius Malunions

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1 SCIENTIFIC ARTICLE Arthroscopically Guided Osteotomy for Management of Intra-Articular Distal Radius Malunions Francisco del Piñal, MD, PhD, Leopoldo Cagigal, MD, Francisco J. García-Bernal, MD, PhD, Alexis Studer, MD, Javier Regalado, MD, Carlos Thams, MD Purpose A malunion with a step-off of 1 mm or more after an intra-articular distal radius fracture may cause pain and arthritic changes at midterm follow-up. We present our technique for treating intra-articular distal radius malunions by carrying out an osteotomy from inside the joint outward under arthroscopic guidance using the dry arthroscopy technique, with emphasis on the clinical and radiologic outcomes. Methods We performed surgery on 11 patients for intra-articular malunion of the distal radius 1 to 5 months after the injury. Preoperative step-offs ranged from 2 to 5 mm (average, 2.5 mm) on plain radiographs. Original fracture patterns involved 1 radial styloid fracture, 1 radiocarpal fracture dislocation, and 9 comminuted intra-articular fractures. In 5 cases an anterior-ulnar or radial styloid fragment was repositioned. In the rest, more than 1 fragment (up to 3) was osteotomized. In 1 patient the articular osteotomy was combined with an ulnar shortening osteotomy. Results Follow-up ranged from 12 to 48 months. Step-offs were reduced in most cases to 0 mm; however, localized gaps ( 2 mm) and cartilage defects were commonly seen intraoperatively because the fragments did not accurately fit. According to the Gartland and Werley score, there were 4 excellent and 7 good results (mean score of 2.8). The Modified Green and O Brien system achieved a mean score of 83, with 3 excellent, 5 good, and 3 fair results. One patient showed radiolunate narrowing on follow-up radiographs. Conclusions Arthroscopically assisted osteotomy permits direct visualization of the osteotomy site with good midterm clinical and radiologic outcomes. The technique can be used in irregularly defined fragments. (J Hand Surg 2010;35A: Published by Elsevier Inc. on behalf of the American Society for Surgery of the Hand.) Type of study/level of evidence Therapeutic IV. Key words Wrist arthroscopy, radius malunion, distal radius osteotomy, dry arthroscopy. UNFAVORABLE RESULTS AND degenerative arthritis may be expected when anatomical reduction is not achieved after distal radius fractures. 1 3 Several authors have pointed out that the goal is anatomical reduction, or at worst a step-off of less than 1 mm. 4 6 From the Instituto de Cirugía Plástica y de la Mano, Private Practice and Hospital Mutua Montañesa, Santander, Spain. Received for publication July 24, 2009; accepted in revised form December 1, No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Francisco del Piñal, MD, PhD, Calderón de la Barca 16-entlo, E Santander, Spain; drpinal@drpinal.com /10/35A $36.00/0 doi: /j.jhsa Management of the young and/or active patient with a step-off after a malunited distal radius fracture includes intra-articular osteotomy, which is nonetheless hampered by limited vision. For volar shearing type malunions, the joint is approached volarly, the external callus is removed, and the osteotomy is directed toward the joint, with the intent that the osteotome follows the original fracture line. 7 9 For other types of intra-articular malunion, the approach is through a dorsal capsular window Fernández 10 considered this technique appropriate only for single line fractures, whereas others 8,12 used it for the more complex 4-part fracture configurations. We investigated the possibility of direct arthroscopic manipulation of the displaced fragments by working Published by Elsevier, Inc. on behalf of the ASSH.

2 INSIDE-OUT OSTEOTOMY FOR RADIUS MALUNIONS 393 TABLE 1. Demographics Case Age Gender Dominance Fracture AO Delay (wk) Previous Treatment 1 46 M D C Cast 2 32 W ND C K-wire external fixator 3 42 M ND C Cast 4 45 M D B Cast 5 45 M ND C K-wire 6 25 M D C Volar plate 7 49 M D C External fixator 8 32 M D C Cast 9 27 M ND B K-wire M D C K-wire external fixator W D C K-wire D, Dominant side; ND, Non-dominant side. inside the joint. 13 We found that the dry procedure without fluid distension of the joint is preferable. 14 In our previous report we showed that the technique was feasible; in this report, we present results of this surgery. The purpose of this retrospective study was to assess the clinical and radiographic outcomes in the management of intra-articular distal radius malunions with an arthroscopically assisted osteotomy. MATERIALS AND METHODS From 2004 to June 2008, we operated on 11 consecutive patients with intra-articular distal radius impacted fractures or malunions with an articular step-off of 2 mm or more measured on plain x-rays using an arthroscopically assisted osteotomy technique. 13 Patients were observeded for at least 12 months after the surgery (mean, 32 mo; range, mo) (Table 1). There were 9 men and 2 women with a mean age of 42 years (range, y). All except 1 (case 8) occurred under workers compensation coverage. Four patients were involved in heavy work; all the rest were performing less demanding manual activities. The dominant hand was affected 7 times. One had a radial styloid fracture, 1 a volar radiocarpal fracture dislocation, and the rest different types of comminuted intra-articular fractures (C31 of the AO classification). 15 Two of the authors measured step-offs and gaps in millimeters with a metric ruler on preoperative plain radiographs. The most displaced fragment was used as a reference when several fragments were involved. Preoperative step-offs ranged from 2 to 5 mm (average, 2.5 mm). Gaps varied from 0 to 3 mm (average, 0.73 mm). Time from the original injury to surgery was 9.6 weeks on average (range, 4 21 wk). All patients had been managed initially elsewhere. Original treatment consisted of closed reduction and cast immobilization in 4 patients, K-wires and cast in 3 patients, closed reduction and external fixator in 1 patient; K-wire and external fixator in 2 patients, and a volar locking plate in 1 patient. Immobilization time ranged from 4 to 6 weeks, except in the patient with the plate (number 6), who started therapy immediately after the surgery. The technique of osteotomy has been described previously (Fig. 1). 13,14 An arthroscopic arthrolysis is first carried out to create working space, as the joint is scarred and unyielding. To cut the bone, we used a shoulder periosteal elevator (of 15 and 30 angles; Arthrex AR and AR ; Arthrex, Naples, FL) and also straight and curved osteotomes (Arthrex AR-1770 and AR-1771). Instruments with different angles were required. To avoid damaging the cartilage or cutting the extensor tendons, the osteotome should have a double 90 twist on its way to the joint cavity. First, it was introduced horizontally in the direction of the skin incision, then it was twisted 90 in the subcutaneous tissue to avoid the extensor tendons, and finally it was rotated again inside the joint itself. Stabilization of the fragments was carried out with volar locking plates when several fragments were mobilized; screws or buttressing plates were used when only one fragment needed to be addressed. Evaluation The patients were seen at varying intervals until discharge by the treating surgeon. For the purpose of this study, they

3 394 INSIDE-OUT OSTEOTOMY FOR RADIUS MALUNIONS FIGURE 1: Correction of a straight line malunion in the scaphoid fossa with a simple straight osteotomy. A The probe (2 mm wide) is sitting on top of the depressed fragment to gauge the deformity. B The osteotome introduced from the 3-4 portal is cutting the malunited scaphoid fossa fragment. C Notice correction of the step-off at the end of the surgery. TABLE 2. Radiology Case Radial Inclination ( ) Volar Angulation ( ) Radial Length (mm) Ulnar Variance (mm) Articular Steps (mm) Articular Gaps (mm) Before After Before After Before After Before After Contralateral Before After Before After Mobilized Fragments dorsal 2 dorsal dorsal dorsal were called back and examined by 1 of the authors. Motion and grip strength were recorded, posteroanterior and lateral radiographs were taken, and a final rating was assigned according to the system of Gartland and Werley 16 and the Mayo modification of the system of Green and O Brien. 17 A Disabilities of the Arm, Shoulder, and Hand questionnaire was administered. Two of the authors measured the final alignment on posteroanterior and lateral radiographs, characterized by radial tilt, volar inclination, ulnar variance, and the maximum articular step-off or gap. Radiographic signs of arthrosis were rated according to the system of Knirk and Jupiter. 1 In this classification, 0 is given when no sign of arthrosis exists; 1 when there is some joint space narrowing; 2 when there is marked narrowing or osteophyte formation; and 3 when there is bone-on-bone contact. We performed statistical evaluation with SPSS Statistics 17.0 software (SPSS, Cary, NC). We used paired t-test to compare preoperative and postoperative radiographic measurements. The confidence interval of the difference was set at 95%. RESULTS Patients were observed for a minimum of 12 months (range, mo). An average of 1.9 fragments (range, 1 3 fragments) needed to be mobilized (Table 2). All the osteotomies were healed without radiographic evidence of osteonecrosis. Cases 4 and 9 only had a fragment that involved the scaphoid and the lunate fossa, respectively, which needed to be mobilized. In 3 patients (cases 2, 10, and 11) who had sustained a C31 fracture, only 1 fragment was mobilized. The radial shortening in these cases was treated by a concomitant open ulna shortening in 1 case (number 11), or accepted in the other 2 as the residual shortening was less than 2 mm (Fig. 2). In the rest, the joint was distorted after C31 fractures and several fragments were cut and repositioned. The arthroscopy did not reveal any major intracarpal or radioulnar ligamentous derangement. Synovitis and partial tears were debrided at the time of the arthrolysis.

4 INSIDE-OUT OSTEOTOMY FOR RADIUS MALUNIONS 395 FIGURE 2: A C This C31 fracture resulted in a relatively well-aligned, albeit incongruent, radius at the lunate and sigmoid fossae (patient 2). Despite the confusing markings in B concerning the ulnar variance depicted by her original surgeon, the axial shortening was approximately 3 mm compared with the healthy side. D Only the anterior-ulnar fragment was osteotomized. Step-offs were completely corrected in all patients, and gaps were not evident on follow-up radiograms. However, from the intraoperative arthroscopic findings, most patients had gaps and/or chondral defects, rarely more than 2 mm, in isolated spots. The average radial inclination changed from 21 preoperatively to 20 postoperatively, and the volar angulation from an average of 1 to 3. Ulnar variance improved on average 2 mm from the preoperative status, whereas there was a difference of 0.7 mm in relation to the normal side (Table 2). Apart from the correction of the step-offs, there were no significant differences between preoperative and postoperative radiological parameters except for ulnar variance (p.008). The final range of motion averaged 59 (range, 45 to 74 ) of wrist extension; 54 (range, 40 to 68 ) of wrist flexion; 18 (range, 8 to 28 ) of radial deviation; 38 (range, 25 to 50 of ulnar deviation); 80 (range 50 to 90 ) of pronation; and 82 (range, 45 to 90 ) of supination. Grip strength was on average 85% of the contralateral side (range, 78% to 100%) (Table 3). The average score according to the system of Gartland and Werley was 2.8 points (range, 0 5 points). According to the modification of the system of Green and O Brien, the average score was 83 points (range, points). Finally, the average score on the Disabilities of the Arm, Shoulder, and Hand questionnaire was 7.6 (range, 0 34). According to the classification of Knirk and Jupiter, 1 5 patients showed no changes, 5 had slight changes, and 1 (patient 6) had grade 2 changes (mean 0.6) (Table 3). All returned to their previous employment and occupations at an average of 13 weeks (range, 6 20 wk). DISCUSSION Arthroscopic intra-articular osteotomy is more complicated than the repair of a simple distal radius fracture. In addition to technical challenges, the joint is scarred, requiring a preliminary arthrolysis. The assistance of another experienced surgeon is invaluable, as the surgery should be kept ideally under a tourniquet time of less than 2 hours. In early malunions the procedure is carried out as presented in the surgical technique: first placement of a plate and then the arthroscopy. 13 For late presenting malunions (more than 3 months old) or in cases in which a high suspicion of carpal ligament injury exists, the approach is reversed. In these cases, we recommend an initial exploratory arthroscopy to assess the quality of the articular cartilage and the integrity of the liga-

5 396 INSIDE-OUT OSTEOTOMY FOR RADIUS MALUNIONS TABLE 3. Outcomes Case Follow-up (mo) Flex/Exten/RD/UD/Pron/Sup ( ) Grip Strength (%) Gartland and Werley Modified Green and O Brien DASH Knirk and Jupiter /68/28/40/90/ /60/18/40/75/ /52/22/42/90/ /74/25/60/90/ /65/15/30/90/ /55/22/30/60/ /55/15/45/90/ /60/15/40/50/ /60/17/36/80/ /45/08/35/80/ /55/18/25/80/ DASH, Disabilities of the Arm, Shoulder, and Hand questionnaire; Flex/Exten/RD/UD/Pron/Sup, flexion/extension/radial deviation/ulnar deviation/pronation/supination. FIGURE 3: Correction of a complex malunion. The scope is in the 6-R portal looking radially, whereas the instruments are coming from the 3-4 portal in a left wrist. The asterisks mark the same spots before and after the osteotomy in the lunate fossa. Notice that although step-offs have been leveled, gaps (highlighted by the lines) are unavoidable in old malunions (compare this with reduction obtained in a young malunion in Fig. 1). A Pre-reduction. B After reduction. ments. If local conditions allow the osteotomy to be carried out, the hand is released from traction and the surgery proceeds as referred to above. The arthroscopic-guided osteotomy is not devised to deal with articular malunions in which major loss of cartilage on the radius surface itself or on the opposing carpals is detected during the arthroscopy. Our functional results are good compared with the prospect of malunited fractures, 1 3,5 but far from a normal wrist. Although our outcomes are slightly better than those of Ring et al, 8 who used an open osteotomy technique, the meaning of those differences is difficult to interpret. A strong argument favoring carrying out the osteotomy as soon as possible is the fact that although stepoffs can be accurately corrected, even in old cases, residual gaps of about 1 mm (at times even more) are unavoidable in fractures seen late (Fig. 3). Limitations of our study include its retrospective nature and the short length of follow-up (mean, 32 mo). A long-term follow-up, prospective clinical study would be beneficial for evaluating the outcomes of this

6 INSIDE-OUT OSTEOTOMY FOR RADIUS MALUNIONS 397 procedure. It is possible that with longer follow-up, further problems such as arthritic changes in the radiocarpal or distal radioulnar joint would appear to worsen the results. Furthermore, considerable arthroscopic expertise is required to perform the procedure because there is minimal working space and orientation is difficult. It is important to understand the intricacies of the dry technique 14,18 to carry out the procedure in a safe and efficient manner. Any accomplished arthroscopist should not have any undue difficulty incorporating the dry technique, but experience is required before the arthroscopist attempts to perform a complex osteotomy case. Only postoperative radiographic measurements were reported and compared in this study. Postoperative computed tomography scan or a second-look arthroscopy would have provided potentially more accurate data. REFERENCES 1. Knirk JL, Jupiter JB. Intra-articular fractures of the distal end of the radius in young adults. J Bone Joint Surg 1986;68A: Bradway JK, Amadio PC, Cooney WP. Open reduction and internal fixation of displaced, comminuted intra-articular fractures of the distal end of the radius. J Bone Joint Surg 1989;71A: Catalano LW III, Cole RJ, Gelberman RH, Evanoff BA, Gilula LA, Borrelli J Jr. Displaced intra-articular fractures of the distal aspect of the radius: long-term results in young adults after open reduction and internal fixation. J Bone Joint Surg 1997;79A: Fernandez DL, Geissler WB. Treatment of displaced articular fractures of the radius. J Hand Surg 1991;16A: Trumble TE, Schmitt SR, Vedder NB. Factors affecting functional outcome of displaced intra-articular distal radius fractures. J Hand Surg 1994;19A: Doi K, Hattori Y, Otsuka K, Abe Y, Yamamoto H. Intra-articular fractures of the distal aspect of the radius: arthroscopically assisted reduction compared with open reduction and internal fixation. J Bone Joint Surg 1999;81A: Thivaios GC, McKee MD. Sliding osteotomy for deformity correction following malunion of volarly displaced distal radial fractures. J Orthop Trauma 2003;17: Ring D, Prommersberger KJ, González del Pino J, Capomassi M, Slullitel M, Jupiter JB. Corrective osteotomy for intra-articular malunion of the distal part of the radius. J Bone Joint Surg 2005;87A: Prommersberger KJ, Ring D, del Pino JG, Capomassi M, Slullitel M, Jupiter JB. Corrective osteotomy for intra-articular malunion of the distal part of the radius: surgical technique. J Bone Joint Surg 2006; 88A(Suppl 1): Fernandez DL. Reconstructive procedures for malunion and traumatic arthritis. Orthop Clin North Am 1993;24: Saffar P. Treatment of distal radial intra-articular malunions. In: Saffar PH, Cooney WP III, eds. Fractures of the distal radius. London: Martin Dunitz, 1995: González del Pino J, Nagy L, González Hernandez E, Bartolome del Valle E. [Intraarticular osteotomies for complex malunited fractures: Indications and surgical technique.] Rev Ortop Traumatol 2000;44: del Piñal F, García-Bernal FJ, Delgado J, Sanmartín M, Regalado J, Cerezal L. Correction of malunited intra-articular distal radius fractures with an inside-out osteotomy technique. J Hand Surg 2006; 31A: del Piñal F, García-Bernal FJ, Pisani D, Regalado J, Ayala H, Studer A. Dry arthroscopy of the wrist: surgical technique. J Hand Surg 2007;32A: Muller ME, Nazarian S, Koch P, Schaftzken J. The comprehensive classification of fractures of long bones. New York: Springer, 1990: Gartland JJ Jr, Werley CW. Evaluation of healed Colles fractures. J Bone Joint Surg 1951;33A: Cooney WP, Bussey R, Dobyns JH, Linscheid RL. Difficult wrist fractures: perilunate fracture-dislocations of the wrist. Clin Orthop Relat Res 1987;214: del Piñal F. Dry arthroscopy of the wrist: its role in the management of articular distal radius fractures. Scand J Surg 2008;97: