LATE RESULTS OF TRANSFER OF THE TIBIAL TUBERCLE FOR RECURRENT DISLOCATION OF THE PATELLA1 W. G. J. HAMPSON nd P. HILL, BRISTOL, ENGLAND The uthors wished to determine the lte results of the Huser opertion, with specil reference to the development of osteorthritis. Predisposing fctors ssocited with recurrent disloction of the ptell were lso investigted. Thirty-five ptients with forty-four surgiclly treted knees ttended for review, ten to twenty-five (verge sixteen) yers fter opertion. Two ptients hd subsequently undergone excision of the ptell. Ten ptients gve fmily history of recurrent disloction of the ptell nd seven ptients showed generlised joint lxity. Pin ws present in eight knees before opertion nd ws present in thirty-three knees (75 per cent) t the time of review. Ptellr crepitus ws present in thirty-seven out of forty-two knees (88 per cent) t review. Osteorthritis ws present in thirty out of forty-two knees (70 per cent). The incidence increses with time since opertion nd the present ge of the ptient. It is concluded tht the Huser opertion prevents further disloction but does not prevent the development of osteorthritis. It is possible tht simple soft-tissue opertion which effectively prevents disloction might chieve the sme results. Ofthe mny opertions devised for recurrent disloction of the ptell, trnsposition of the tibil tubercie with lterl relese nd medil pliction (Huser 1938) remins probbly the most widely used. It is ccepted by mny uthors tht this opertion is successful in preventing further disloction, though there hs been no survey bsed on follow-up for more thn ten yers. Hrrison (1955) suggested, on very limited evidence, tht repositioning of the ptell might hlt or even reverse the degenertive process, clim tht ws supported by Heywood (1961), Bowker nd Thompson (1964) nd Hughston (1968). In contrst Mcnb (1952) believed tht once degenertive chnge hd occurred only ptellectomy would prevent progressive osteorthritis. The principl im of this study, therefore, ws to determine the lte results of the opertion, with specil reference to the development of osteorthritis. Predisposing fctors ssocited with recurrent disloction of the ptell were lso investigted. 7 6 13 12 11 10 Yers since Opertion FIG. 1 The distribution of time in yers since opertion. CLINICAL MATERIAL The documents were vilble of fifty-two ptients whose clinicl records clerly confirmed tretment by Huser opertion more thn ten yers previously. From this totl, thirty-five ptients, with forty-four surgiclly treted knees, ttended for review. The verge time since opertion ws sixteen yers, the rnge being from ten to twenty-five yers (Fig. 1). The ge t the first disloction verged fourteen yers nd vried from three to forty-three yers (Fig. 2). The intervl from first disloction to opertion vried from less thn one yer to twenty-six yers, nd verged 1. Age t Onset of lisloction FIG. 2 The ge t onset of recurrent disloction. six yers (Fig. 3). The ge t opertion rnged from twelve to forty-six yers with n verge of twenty-one yers (Fig. 4). Tble I shows tht this clinicl mteril is similr to tht reviewed by previous uthors. 1 Pper presented t the spring meeting of the British Orthopedic Assocition in Bristol in April 1973. W. G. J. Hmpson, F.R.C.S.Ed., Bristol Royl Infirmry, Bristol BS2 8HW. P. Hill, F.R.C.S., F.R.A.C.S., The Croft, 57 Brlston Old Rod, Trenthm, Stoke-on-Trent, Englnd. VOL. 57-B, No. 2, MAY 1975 209 8
210 W. G. J. HAMPSON AND P. HILL 12! Veors from Onset to Operotion FIG. 3 The time intervl between onset of disloctions nd opertion. METHOD OF ASSESSMENT At interview the ptients were questioned bout ny fmily history of recurrent disloction of the ptell. Their symptoms were determined, prticulr ttention being pid to : 1) pin in the knee (prt from tht ssocited with ctul disloction) ; 2) the frequency nd totl number of disloctions ; nd 3) the extent of instbility or giving wy without ctul disloction. The replies were grded nd compred with the symptoms s recollected before opertion. In most instnces the ltter differed little from those recorded in the hospitl notes. At the clinicl exmintion prticulr note ws mde of retro-ptellr crepitus, ptellr lxity nd genu vlgum. The ptient s bility to stnd unsupported on the semiflexed knee ws checked. An ssessment of generlised hypermobility involved exmining the knees, thumbs, fingers, elbows nd nkles, s described by Crter nd Age t Opertion FIG. 4 The ge distribution t time of opertion. Wilkinson (1964). Three bnormlly mobile joints were tken s evidence of generlised joint lxity. Rdiogrphs were tken of both knees nd included tngentil views of the ptello-femorl joint in 40 degrees of flexion (Mcnb 1952) in order to ssess ptellofemorl rthritis. The findings were grded s mild, moderte or severe (Tble II). Finlly, downwrd nd medil displcement of the ptell ws mesured from the rdiogrphs in the thirty-five cses in which unilterl opertion llowed comprison with the opposite knee (Figs. 5 nd 6). RESULTS Predisposing fctors-ten ptients gve fmily history of recurrent disloction of the ptell, six of these hving more thn one reltive ffected. A strong fmilil TABLE REPORTED CASES OF TREATED RECURRENT DISLOCATION OF THE PATELLA I Author of ptients of knees Mle Femle Bilterl Hypermobile ptell Generlised hypermobility of ptients with fmily history Age t first disloction Intervl from onset to opertion (yers) of knees reviewed over 10 yers Bowker nd Thompson 48 65 12 25 percent 36 75 percent 17 32 out of 37 percent 47 68 percent 5 out of 47 10 percent 12 out of 48 25 percent 3-50 Averge 14 0 to 46 Averge 10 7 Hmpson nd Hill 35 44 13 38 percent 22 62 percent 9 26 percent 25 out of 42 60 per cent 7 out of 35 20 per cent 4 with bilterl disloction 10 out of 35 30 per cent 4 with bilterl disloction 3-43 Averge 14 0 to 26 Averge 6 44 Hrrison 26 30 4 13 per cent 3-34 Averge I 5 2 to 20 Averge 6 10 Heywood 76 90 14 16 percent 30 out of 54 56percent 19 out of 54 35percent 2-36 Averge 14 17 Mcnb 46 64 6 13 percent 40 87 percent 18 28 percent 3-21 Averge 13 Averge 7 10 (Over 8 yers) 1 Some cses reported by other uthors were not treted by Huser opertions. THE JOURNAL OF BONE AND JOINT SURGERY
LATE RESULTS OF TRANSFER OF THE TIBIAL TUBERCLE FOR RECURRENT DISLOCATION OF THE PATELLA 211 incidence s noted by Bowker nd Thompson (1964) (Tble I) is therefore confirmed. Seven ptients hd generlised joint lxity, confirming the findings of Heywood (1961) nd of Bowker nd Thompson (1964) (Tble I). Only one of the ptients with generlised joint lxity hd fmily history of recurrent disloction of the ptell. twenty-five knees ptello-femorl rthritis ws the more severe. The incidence of osteorthritis in reltion to the present ge of the ptient is shown in Figure 9. It cn TABLE II GRADING OF RADIOLOGICAL OSTEOARTHRITIS OF THE KNEE Grde Clinicl fetures Nil Norml knee joint Mild Minor osteophyte formtion nd/or slight reduction in crtilge spce Moderte Mrked loss of crtilge spce, but without collpse of subchondrl bone Severe Gross osteorthritis The only exmples of genu vlgum were in two ptients with gross osteorthritis. The importnce of this fctor in the pthogenesis of recurrent disloction of the ptell my therefore hve been over-emphsised. Subjective ssessment-pin in the knees s recollected before opertion nd t time of review is compred in Figure 7. It cn be seen tht wheres only eight knees gve mild or moderte pin before opertion, thirty-three knees (75 per cent) were pinful t the time of review; in two cses this pin ws severe. The eight knees giving pin before opertion did not show ny greter incidence of osteorthritis t review thn did the other knees in this smll series. A feeling of insecurity, or episodes of giving wy, s remembered before opertion nd gin t review, re grded nd compred in Figure 8. It cn be seen tht opertion did not significntly ffect these symptoms. forty-four. Disloction hd recurred in only one knee out of the Objective ssessment-only forty-two knees were vilble for nlysis t the time of this study becuse the ptell hd been subsequently excised in two ptients, in one for severe pin nd in the other for recurrent disloction. Retro-ptellr crepitus ws present in thirty-seven knees (88 per cent), being of moderte intensity in twelve nd severe in two. Kneeling ws uncomfortble in seventeen of the knees operted upon (s ginst three of the twenty-six not operted upon). Six ptients could not stnd unsupported on the semi-flexed knee. Rdiologicl ssessment-rdiogrphs showed osteorthritis in thirty out of the forty-two knees (70 per cent). There ws ptello-femorl rthritis in thirty knees, moderte in four nd severe in two. Osteorthritis of the tibio-femorl comprtment ws present in twenty knees, moderte in two nd severe in one. In five knees tibio-femorl rthritis predominted, but in the remining FIG. 6 Figure 5-A line is drwn upwrds from the lterl rticulr mrgin of the tibi, perpendiculr to the tibil plteu. From this reference line the medil displcement of the ptell in the surgiclly treted knee is determined by comprison with the ptellr position in the knee not operted upon. Figure 6-Downwrd displcement of the ptell is determined by compring the distnce between the lower border of the rticulr surfce of the ptell nd the tibil plteu in the knee not operted upon nd tht in the knee operted upon, the rdiogrphs being tken with both knees flexed to 40 degrees. be seen tht the proportion of degenerte joints increses from five out of fifteen knees under thirty yers to eleven out of thirteen over the ge of forty. All eight moderte or severe exmples of osteorthritis re included in the ltter group. VOL. 57-B, No. 2, MAY 1975
212 W. G. J. HAMPSON AND P. HILL 36 Pin before Opertion Pin t Review LI Insecurity before Opertion I Insecurity t Review Grde 0: No Instbility $1 Grde 0: No Pin Grde 1 : Mild Pin Grde 2: Moderte Pin ( I - E Grde 1 : Insecurity or Occsionl GivingWy (<Once/Month) Grde 2 :GivingWy (>Once/Month) Grde 3 Giving Wy 1 Once/Week Grde 3 : Severe Pin Grde 0 Grde 1 Grde 2 Grde 3 FIG. 7 The grding of pin s recollected before opertion nd t time of review. Grde 0 Grde 1 Grde 2 Grde 3 FIG. 8 The distribution of insecurity or episodes of giving wy s recollected before opertion nd t time of review. Osteorthrit teorthrit is is U,,.,. E Lessthn 3l-!O 41-50 More thn 30 50 Age in Yers FIG. 9 The incidence of osteorthritis compred with the ptient s ge t time of review. Less thn 16 l6nd Over Yers since Opertion FIG. 10 The incidence of osteorthritis in knees reviewed less thn sixteen yers fter opertion nd in those reviewed t sixteen yers nd lter. THE JOURNAL OF BONE AND JOINT SURGERY
LATE RESULTS OF TRANSFER OF THE TIBIAL TUBERCLE FOR RECURRENT DISLOCATION OF THE PATELLA 213 The incidence of osteorthritis in reltion to time since opertion is shown in Figure 10. While only hlf of the ptients seen less thn sixteen yers fter opertion hd osteorthritis, nerly ll ptients reviewed t sixteen yers nd lter were ffected. Medil displcement of the ptell rnged from 02 to 32 centimetres with medin distnce of ll centimetres. Downwrd displcement rnged from 0-2 to 2-8 centimetres, with medin distnce of l0 centimetre. DISCUSSION The most striking finding of this long-term study is the clinicl nd rdiologicl evidence of progressive degenertion of the knee joint fter opertion nd with incresing ge of the ptient. We re therefore unble to support the suggestion of Hrrison (1955), Heywood (1961), Bowker nd Thompson (1964) nd Hughston (1968) tht Huser opertions prevent or slow down degenertion. We do not consider tht these uthors hve sufficient number oflong-term results on which to support their rgument. Moreover, the limited long-term findings pper to suggest deteriortion of function of the knee. Hrrison (1955) tht six out of ten knees operted on more thn ten yers before review gve discomfort or n che, while Heywood (1961) reported eight out of seventeen knees with unstisfctory results ten yers nd more fter opertion. On the other hnd, in our series, neither the frequency of disloction before opertion nor degree of ptellr displcement chieved t opertion ppered to influence the long-term results. The ssocited generlised joint lxity might suggest tht these re dysplstic joints in which ptellr disloction highlights one feture of generlised condition. The significnce of strong fmilil tendency to recurrent disloction with or without generlisedjoint lxity (Crter nd Sweetnm 1958), needs further study. The uthors wish to thnk the surgeons of Hrlow Wood nd Winford Orthopedic Hospitls for permission to include their cses, nd in prticulr Mr W. Wugh who first suggested this study to us. We re lso indebted to Mr A. H. C. Rtliff for dvice nd encourgement during the preprtion of this pper. REFERENCES Bowker, J. H., nd Thompson, E. B. (1964) Surgicl tretment of recurrent disloction of the ptell. Journl of Bone nd Joint Surgery, 46-A, 1451-1461. Crter, C., nd Sweetnm, R. (1958) Fmilil joint lxity nd recurrent disloction of the ptell. Journl of Bone nd Joint Surgery, 40-B, 664-667. Crter, C., nd Wilkinson, J. (1964) Persistent joint lxity nd congenitl disloction of the hip. Journl of Bone nd Joint Surgery, 46-B, 40-45. Hrrison, M. H. M. (1955) The results of relignment opertion for recurrent disloction ofthe ptell. JournlofBone ndjoint Surgery, 37-B, 559-567. Huser, E. D. W. (1938) Totl tendon trnsplnt for slipping ptell. Surgery, Gynecology nd Obstetrics, 66, 199-2 14. Heywood, A. W. B (1961) Recurrent disloction of the ptell. Journl ofbone nd Joint Surgery, 43-B, 508-5 17. Hughston, J. C. (1968) Subluxtion of the ptell. Journl ofbone ndjoint Surgery, 50-A, 1003-1026. Mcnb, I. (1952) Recurrent disloction of the ptell. Journl ofbone nd Joint Surgery, 34-A, 957-967. VOL. 57-B, No. 2, MAY 1975