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The Bone & Joint Journal
Vol. 101-B, Issue 10 | Pages 1230 - 1237
1 Oct 2019
Kayani B Konan S Horriat S Ibrahim MS Haddad FS

Aims. The aim of this study was to assess the effect of posterior cruciate ligament (PCL) resection on flexion-extension gaps, mediolateral soft-tissue laxity, fixed flexion deformity (FFD), and limb alignment during posterior-stabilized (PS) total knee arthroplasty (TKA). Patients and Methods. This prospective study included 110 patients with symptomatic osteoarthritis of the knee undergoing primary robot-assisted PS TKA. All operations were performed by a single surgeon using a standard medial parapatellar approach. Optical motion capture technology with fixed femoral and tibial registration pins was used to assess gaps before and after PCL resection in extension and 90° knee flexion. Measurements were made after excision of the anterior cruciate ligament and prior to bone resection. There were 54 men (49.1%) and 56 women (50.9%) with a mean age of 68 years (. sd. 6.2) at the time of surgery. The mean preoperative hip-knee-ankle deformity was 4.1° varus (. sd. 3.4). Results. PCL resection increased the mean flexion gap significantly more than the extension gap in the medial (2.4 mm (. sd. 1.5) vs 1.3 mm (. sd. 1.0); p < 0.001) and lateral (3.3 mm (. sd. 1.6) vs 1.2 mm (. sd. 0.9); p < 0.01) compartments. The mean gap differences after PCL resection created significant mediolateral laxity in flexion (gap difference: 1.1 mm (. sd. 2.5); p < 0.001) but not in extension (gap difference: 0.1 mm (. sd. 2.1); p = 0.51). PCL resection significantly improved the mean FFD (6.3° (. sd. 4.4) preoperatively vs 3.1° (. sd. 1.5) postoperatively; p < 0.001). There was a strong positive correlation between the preoperative FFD and change in FFD following PCL resection (Pearson’s correlation coefficient = 0.81; p < 0.001). PCL resection did not significantly affect limb alignment (mean change in alignment: 0.2° valgus (. sd. 1.2); p = 0.60). Conclusion. PCL resection creates flexion-extension mismatch by increasing the flexion gap more than the extension gap. The increase in the lateral flexion gap is greater than the increase in the medial flexion gap, which creates mediolateral laxity in flexion. Improvements in FFD following PCL resection are dependent on the degree of deformity before PCL resection. Cite this article: Bone Joint J 2019;101-B:1230–1237


The Bone & Joint Journal
Vol. 102-B, Issue 2 | Pages 227 - 231
1 Feb 2020
Lee SH Nam DJ Yu HK Kim JW

Aims. The purpose of this study was to evaluate the relationships between the degree of injury to the medial and lateral collateral ligaments (MCL and LCL) and associated fractures in patients with a posterolateral dislocation of the elbow, using CT and MRI. Methods. We retrospectively reviewed 64 patients who presented between March 2009 and March 2018 with a posterolateral dislocation of the elbow and who underwent CT and MRI. CT revealed fractures of the radial head, coronoid process, and medial and lateral humeral epicondyles. MRI was used to identify contusion of the bone and collateral ligament injuries by tear, partial or complete tear. Results. A total of 54 patients had a fracture; some had more than one. Radial head fractures were found in 25 patients and coronoid fractures in 42. Lateral and medial humeral epicondylar fractures were found in eight and six patients, respectively. Contusion of the capitellum was found in 43 patients and rupture of the LCL was seen in all patients (partial in eight and complete in 56), there was complete rupture of the MCL in 37 patients, partial rupture in 19 and eight had no evidence of rupture. The LCL tear did not significantly correlate with the presence of fracture, but the MCL rupture was complete in patients with a radial head fracture (p = 0.047) and there was significantly increased association in those without a coronoid fracture (p = 0.015). Conclusion. In posterolateral dislocation of the elbow, LCL ruptures are mostly complete, while the MCL exhibits various degrees of injury, which are significantly associated with the associated fractures. Cite this article: Bone Joint J 2020;102-B(2):227–231


Bone & Joint Research
Vol. 4, Issue 3 | Pages 38 - 44
1 Mar 2015
Thornton GM Reno CR Achari Y Morck DW Hart DA

Objectives. Ligaments which heal spontaneously have a healing process that is similar to skin wound healing. Menopause impairs skin wound healing and may likewise impair ligament healing. Our purpose in this study was to investigate the effect of surgical menopause on ligament healing in a rabbit medial collateral ligament model. Methods. Surgical menopause was induced with ovariohysterectomy surgery in adult female rabbits. Ligament injury was created by making a surgical gap in the midsubstance of the medial collateral ligament. Ligaments were allowed to heal for six or 14 weeks in the presence or absence of oestrogen before being compared with uninjured ligaments. Molecular assessment examined the messenger ribonucleic acid levels for collagens, proteoglycans, proteinases, hormone receptors, growth factors and inflammatory mediators. Mechanical assessments examined ligament laxity, total creep strain and failure stress. Results. Surgical menopause in normal medial collateral ligaments initiated molecular changes in all the categories evaluated. In early healing medial collateral ligaments, surgical menopause resulted in downregulation of specific collagens, proteinases and inflammatory mediators at 6 weeks of healing, and proteoglycans, growth factors and hormone receptors at 14 weeks of healing. Surgical menopause did not produce mechanical changes in normal or early healing medial collateral ligaments. With or without surgical menopause, healing ligaments exhibited increased total creep strain and decreased failure stress compared with uninjured ligaments. Conclusions. Surgical menopause did not affect the mechanical properties of normal or early healing medial collateral ligaments in a rabbit model. The results in this preclinical model suggest that menopause may result in no further impairment to the ligament healing process. . Cite this article: Bone Joint Res 2015;4:38–44


The Journal of Bone & Joint Surgery British Volume
Vol. 84-B, Issue 6 | Pages 846 - 851
1 Aug 2002
Gupte CM Smith A McDermott ID Bull AMJ Thomas RD Amis AA

The meniscofemoral ligaments were studied in 84 fresh-frozen knees from 49 cadavers. Combined anterior and posterior approaches were used to identify the ligaments. In total, 78 specimens (93%) contained at least one meniscofemoral ligament. The anterior meniscofemoral ligament (aMFL) was present in 62 specimens (74%), and the posterior meniscofemoral ligament (pMFL) in 58 (69%). The 42 specimens (50%) in which both ligaments were present were from a significantly younger population than that with one MFL or none (p < 0.05). Several anatomical variations were identified, including oblique fibres of the posterior cruciate ligament (PCL), which were seen in 16 specimens (19%). These were termed the ‘false pMFL’. The high incidence of MFLs and their anatomical variations should be borne in mind during arthroscopic and radiological examination of the PCL. It is important to recognise the oblique fibres of the PCL on MRI in order to avoid wrongly identifying them as either a pMFL or a tear of the lateral meniscus. The increased incidence of MFLs in younger donors suggests that they degenerate with age


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 10 | Pages 1397 - 1402
1 Oct 2010
Nada AN Debnath UK Robinson DA Jordan C

We describe the clinical outcome of a technique of surgical augmentation of chronic massive tears of the rotator cuff using a polyester ligament (Dacron) in 21 symptomatic patients (14 men, seven women) with a mean age of 66.5 years (55.0 to 85.0). All patients had MRI and arthroscopic evidence of chronic massive tears. The clinical outcome was assessed using the Constant and Murley and patient satisfaction scores at a mean follow-up of 36 months (30 to 46). The polyester ligament (500 mm × 10 mm) was passed into the joint via the portal of Neviaser, medial to the tear through healthy cuff. The two ends of the ligament holding the cuff were passed through tunnels made in the proximal humerus at the footprint of the insertion of the cuff. The ligament was tied with a triple knot over the humeral cortex. All the patients remained free from pain (p < 0.001) with improvement in function (p < 0.001) and range of movement (p < 0.001). The mean pre-operative and post-operative Constant scores were 46.7 (39.0 to 61.0) and 85.4 (52.0 to 96.0), respectively (p < 0.001). The mean patient satisfaction score was 90%. There were two failures, one due to a ruptured ligament after one year and the other due to deep-seated infection. The MR scan at the final follow-up confirmed intact and thickened bands in 15 of 17 patients. This technique of augmentation gives consistent relief from pain with improved shoulder movement in patients with symptomatic massive tears of the rotator cuff


The Journal of Bone & Joint Surgery British Volume
Vol. 81-B, Issue 4 | Pages 636 - 642
1 Jul 1999
Shahane SA Ibbotson C Strachan R Bickerstaff D

We designed an experimental study to prove the existence of the popliteofibular ligament (PFL) and to define its role in providing static stability of the knee. We also examined the contribution of the lateral collateral ligament (LCL). We found this ligament to be present in all eight human cadaver knees examined. These specimens were mounted on a specially designed rig and subjected to posterior, varus and external rotational forces. We used the technique of selective sectioning of ligaments and measured the displacement with a constant force applied, before and after its division. We recorded the displacement in primary posterior translation, coupled external rotation, primary varus angulation and primary external rotation. Statistical analysis using the standard error of the mean by plotting 95% confidence intervals, was used to evaluate the results. The PFL had a significant role in preventing excessive posterior translation and varus angulation, and in restricting excessive primary and coupled external rotation. Isolated section of the belly of popliteus did not cause significant posterolateral instability of the knee. The LCL was also seen to act as a primary restraint against varus angulation and secondary restraint against external rotation and posterior displacement. Our findings showed that in knees with isolated disruption of the PFL stability was restored when it was reconstructed. However in knees in which the LCL was also disrupted, isolated reconstruction of the PFL did not restore stability


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 5 | Pages 614 - 618
1 May 2008
Ruch DS Shen J Chloros GD Krings E Papadonikolakis A

Contracture of the collateral ligaments is considered to be an important factor in post-traumatic stiffness of the elbow. We reviewed the results of isolated release of the medial collateral ligament in a series of 14 patients with post-traumatic loss of elbow flexion treated between 1998 and 2002. There were nine women and five men with a mean age of 45 years (17 to 76). They were reviewed at a mean follow-up of 25 months (9 to 48). The operation was performed through a longitudinal posteromedial incision centred over the ulnar nerve. After decompression of the ulnar nerve, release of the medial collateral ligament was done sequentially starting with the posterior bundle and the transverse component of the ligament, with measurement of the arc of movement after each step. If full flexion was not achieved the posterior half of the anterior bundle of the medial collateral ligament was released. At the latest follow-up, the mean flexion of the elbow improved significantly from 96° (85° to 115°) pre-operatively to 130° (110° to 150°) at final follow-up (p = 0.001). The mean extension improved significantly from 43° (5° to 90°) pre-operatively to 22° (5° to 40°) at final follow-up (p = 0.003). There was a significant improvement in the functional outcome. The mean Broberg and Morrey score increased from a mean of 54 points (29.5 to 85) pre-operatively to 87 points (57 to 99) at final follow-up (p < 0.001). All the patients had normal elbow stability. Our results indicate that partial surgical release of the medial collateral ligament is associated with improved range of movement of the elbow in patients with post-traumatic stiffness, but was less effective in controlling pain


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 7 | Pages 893 - 899
1 Jul 2006
Petrou G Chardouvelis C Kouzoupis A Dermon A Petrou H Tilkeridis C Gavras M

We carried out a prospective study of 71 patients who had undergone reconstruction of the anterior cruciate ligament with the ABC scaffold. Their mean age was 28 years (18 to 50). All had either sub-acute or chronic traumatic deficiency of the ligament. The mean period of follow-up was five years (four to seven). Assessment included the use of the International Knee Documentation Committee score, the modified Lysholm score, the Tegner Activity score, the Knee Injury and Osteoarthritis Outcome score and measurement with the KT-1000 arthrometer. Two patients had mild recurrent synovitis. There were no infections and no failures of the ligament. During the period of study, two patients sustained a traumatic fracture of a femoral condyle. The implants retained their integrity in both cases. All patients returned to their previous or enhanced levels of daily activity by three months after operation and 56 (79%) achieved their pre-injury level of sporting activity by six months. The patients who were competing in National level sports returned to play at one level less after operation than before. The Lysholm score showed that 58% of the patients (41) were excellent, 34% (24) good, and 8% (6) fair, with a mean post-operative score of 93. According to the International Knee Documentation Committee score, 35% of knees (25) were ‘normal’, 52% (37) ‘nearly normal’ and 13% (9) ‘abnormal’. Complete satisfaction was noted in 90% of patients (64). The development of osteoarthritis and the management of anterior cruciate deficiency associated with laxity of the medial collateral ligament remains uncertain. Our results indicate that in the medium-term, the ABC ligament scaffold is suitable and effective when early and safe return to unrestricted activities is demanded. We acknowledge the current general hostility towards reconstruction of the anterior cruciate ligament with artificial materials following reports of early failure and chronic synovitis associatiated with the production of particulate debris. We did not encounter these problems


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 7 | Pages 883 - 886
1 Jul 2006
Archbold HAP Mockford B Molloy D McConway J Ogonda L Beverland D

Ensuring the accuracy of the intra-operative orientation of the acetabular component during a total hip replacement can be difficult. In this paper we introduce a reproducible technique using the transverse acetabular ligament to determine the anteversion of the acetabular component. We have found that this ligament can be identified in virtually every hip undergoing primary surgery. We describe an intra-operative grading system for the appearance of the ligament. This technique has been used in 1000 consecutive cases. During a minimum follow-up of eight months the dislocation rate was 0.6%. This confirms our hypothesis that the transverse acetabular ligament can be used to determine the position of the acetabular component. The method has been used in both conventional and minimally-invasive approaches


The Journal of Bone & Joint Surgery British Volume
Vol. 91-B, Issue 9 | Pages 1178 - 1182
1 Sep 2009
Hakki S Coleman S Saleh K Bilotta VJ Hakki A

The requirement for release of collateral ligaments to achieve a stable, balanced total knee replacement has been reported to arise in about 50% to 100% of procedures. This wide range reflects a lack of standardised quantitative indicators to determine the necessity for a release. Using recent advances in computerised navigation, we describe two navigational predictors which provide quantitative measures that can be used to identify the need for release. The first was the ability to restore the mechanical axis before any bone resection was performed and the second was the discrepancy in the measured medial and lateral joint spaces after the tibial osteotomy, but before any femoral resection. These predictors showed a significant association with the need for collateral ligament release (p < 0.001). The first predictor using the knee stress test in extension showed a sensitivity of 100% and a specificity of 98% and the second, the difference between medial and lateral gaps in millimetres, a sensitivity of 83% and a specificity of 95%. The use of the two navigational predictors meant that only ten of the 93 patients required collateral ligament release to achieve a stable, neutral knee


The Journal of Bone & Joint Surgery British Volume
Vol. 80-B, Issue 5 | Pages 785 - 790
1 Sep 1998
Sugimoto K Samoto N Takaoka T Takakura Y Tamai S

We treated 43 acute tears of the calcaneofibular ligament by operation in 43 patients after subtalar arthrography. There were 22 men and 21 women with a mean age of 22.3 years (14 to 61). Anteroposterior (AP), lateral and oblique views were obtained with the foot in 45° of internal rotation and the ankle in the neutral position. Any communication or leakage to the ankle, tendon sheaths, subcutaneous tissue and sinus tarsi was recorded. We examined an oblique view of the microrecess along the interosseous ligament and an AP view of the lateral recess just under the distal end of the fibula. We also studied a control group of 27 patients with isolated injuries of the anterior talofibular ligament without rupture of the calcaneofibular ligament. The findings in the two groups were significantly different when examined for leakage to the ankle (p = 0.0002), to the peroneal tendon sheaths (p = 0.0347) and to the subcutaneous tissue (p = 0.0222), absence of the microrecess (p = 0.0055) and presence of the lateral recess (p = 0.0012). Many ankle sprains which involve tearing of the calcaneofibular ligament are accompanied by injuries of the subtalar joint. Combined injuries of the anterior talofibular ligament and calcaneofibular ligament, and isolated injury of the anterior talofibular ligament should be differentiated


The Journal of Bone & Joint Surgery British Volume
Vol. 76-B, Issue 1 | Pages 147 - 149
1 Jan 1994
Sennwald G Zdravkovic V Oberlin C

The palmar ligaments of the wrist were dissected in 15 adult cadaver wrists and demonstrated by MRI in three. Ten fetal wrists (10 to 19 weeks' gestation) were studied in histological sections. The palmar scaphotriquetral ligament was found in them all. Its attachment to the triquetrum is substantial but that to the scaphoid is thin and fan-shaped, its fibres interdigitating with those of the radioscaphocapitate ligament. The contribution of the ligament to carpal stability has yet to be studied, but it may help to support the head of the capitate when the wrist is dorsiflexed


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 10 | Pages 1323 - 1327
1 Oct 2008
Kim S Lee D Kim T Choi N

We present the operative technique and clinical results of concomitant reconstruction of the medial collateral ligament (MCL) and the posterior oblique ligament for medial instability of the knee using autogenous semitendinosus tendon with preservation of the tibial attachment. The semitendinosus tendon graft between the screw on the medial epicondyle and the tibial attachment of the graft was overlapped by the MCL, while the graft between the screw and the insertion of the direct head of the semimembranosus tendon was overlapped by the central arm of the posterior oblique ligament. Assessment was by stress radiograph and the Lysholm knee scoring scale. After a mean follow-up of 52.6 months (25 to 92), the medial joint opening of the knee was within 2 mm in 22 of 24 patients. The mean Lysholm score was 91.9 (80 to 100). Concomitant reconstruction of the MCL and posterior oblique ligament using autogenous semitendinosus tendon provides a good solution to medial instability


The Bone & Joint Journal
Vol. 97-B, Issue 4 | Pages 484 - 491
1 Apr 2015
van Arkel RJ Amis AA Cobb JP Jeffers JRT

In this in vitro study of the hip joint we examined which soft tissues act as primary and secondary passive rotational restraints when the hip joint is functionally loaded. A total of nine cadaveric left hips were mounted in a testing rig that allowed the application of forces, torques and rotations in all six degrees of freedom. The hip was rotated throughout a complete range of movement (ROM) and the contributions of the iliofemoral (medial and lateral arms), pubofemoral and ischiofemoral ligaments and the ligamentum teres to rotational restraint was determined by resecting a ligament and measuring the reduced torque required to achieve the same angular position as before resection. The contribution from the acetabular labrum was also measured. Each of the capsular ligaments acted as the primary hip rotation restraint somewhere within the complete ROM, and the ligamentum teres acted as a secondary restraint in high flexion, adduction and external rotation. The iliofemoral lateral arm and the ischiofemoral ligaments were primary restraints in two-thirds of the positions tested. Appreciation of the importance of these structures in preventing excessive hip rotation and subsequent impingement/instability may be relevant for surgeons undertaking both hip joint preserving surgery and hip arthroplasty. Cite this article: Bone Joint J 2015; 97-B:484–91


The Journal of Bone & Joint Surgery British Volume
Vol. 32-B, Issue 3 | Pages 396 - 402
1 Aug 1950
Jack EA

Rupture of a ligament usually occurs along a definite line, but is associated with considerable intrinsic damage to the remote parts of the ligament. In spite of this, healing occurs by regeneration of regular collagen to form a new ligament with good tensile strength, provided the ends of the torn ligament are in reasonable apposition, and provided the blood supply is adequate. When lateral instability of the knee after a recent injury suggests that a collateral ligament has been ruptured, wide displacement of the torn ends should be suspected. Accurate replacement can be guaranteed only by surgical intervention; operative repair therefore seems to be justifiable on anatomical grounds. If operation is contemplated it should be undertaken within the first week after injury when it is easy to achieve accurate repair, which later becomes impossible because of shrinkage and friability of the tissue. In order to preserve blood supply, the areolar covering should be disturbed as little as possible, and the least possible amount of fine suture material should be used to anchor the torn ends in position. Nevertheless when the tear involves the upper attachment, ischaemia of the damaged ligament may prevent normal healing, whatever the treatment adopted


The Journal of Bone & Joint Surgery British Volume
Vol. 71-B, Issue 4 | Pages 566 - 570
1 Aug 1989
Fujikawa K Iseki F Seedhom B

The healing of anterior cruciate ligaments reconstructed with the Leeds-Keio artificial ligament was observed by arthroscopy in 42 knees and biopsy in 19 knees at intervals from 3 to 24 months after implantation. By three months the implant was covered with immature new tissue, and a dense vascular network crossed its surface. At 12 months a new ligament had developed and matured, looking like the natural one in most cases. Histology at this stage showed abundant collagenous fibres running parallel and longitudinally, while the synovial membrane showed no more than very slight inflammatory changes. By 18 to 24 months, the new ligament often had the arthroscopic appearance of a normal anterior cruciate ligament. These results suggest that this scaffold type of artificial ligament is effective for cruciate reconstruction, giving satisfactory healing without significant complications


The Journal of Bone & Joint Surgery British Volume
Vol. 77-B, Issue 2 | Pages 219 - 224
1 Mar 1995
Michelson J Hutchins C

Chronic ankle instability after ligamentous injuries has been attributed to loss of proprioception, but there has been no previous study of the mechanoreceptors in human ligaments at this joint. We have examined the ligaments from five cadaver ankles for mechanoreceptors and classified them into the four types described by Wyke and Freeman in their study of feline ligaments. Type-II receptors, thought to provide the sensation of the beginning of joint motion, and type-III receptors, thought to be activated at the extremes of movement, were the most common. Our findings provide some neuroanatomical data to validate further research into the use of proprioceptive training after ligamentous injuries about the ankle


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 10 | Pages 1375 - 1379
1 Oct 2005
Mizuno J Nakagawa H Song J

Seven men with a mean age of 63.9 years (59 to 67) developed dysphagia because of oesophageal compression with ossification of the anterior longitudinal ligament (OALL) and radiculomyelopathy due to associated stenosis of the cervical spine. The diagnosis of OALL was made by plain lateral radiography and classified into three types; segmental, continuous and mixed. Five patients had associated OALL in the thoracic and lumbar spine without ossification of the ligamentum flavum. All underwent removal of the OALL and six had simultaneous decompression by removal of ossification of the posterior longitudinal ligament or a bony spur. All had improvement of their dysphagia. Because symptomatic OALL may be associated with spinal stenosis, precise neurological examination is critical. A simultaneous microsurgical operation for patients with OALL and spinal stenosis gives good results without serious complications


The Journal of Bone & Joint Surgery British Volume
Vol. 85-B, Issue 5 | Pages 671 - 674
1 Jul 2003
Straw R Kulkarni S Attfield S Wilton TJ

We report the results of a prospective randomised trial which assessed the role of the posterior cruciate ligament (PCL) following total knee replacement (Genesis I; Smith and Nephew, Memphis, Tennessee). Over a four-year period, 211 patients underwent total knee replacement by the senior author (TJW). They were randomised at surgery to have the PCL either retained, excised or substituted with a posterior stabilised insert. If it was not possible to retain the ligament due to soft-tissue imbalance, it was released from its tibial insertion until suitable tension was obtained. This created a fourth group, those who were intended preoperatively to have the ligament retained, but in whom it was partially released as a result of findings at the time of surgery. All patients were evaluated using the Knee Society rating system (adapted from Insall). A total of 188 patients (212 knees) was available for follow-up at a mean of 3.5 years after surgery. Preoperatively, there was a varus deformity in 191 knees (90%) and a valgus deformity in 21 (10%). There were no statistical differences in the knee or function scores or the range of movement between the excised, retained and substituted groups. There were, however, significantly worse knee and function scores in the group in whom the PCL was released (p = 0.002)


The Journal of Bone & Joint Surgery British Volume
Vol. 44-B, Issue 4 | Pages 869 - 879
1 Nov 1962
Stener B

1. The pathological anatomy of total rupture of the ulnar collateral ligament of the metacarpo-phalangeal joint of the thumb has been studied at operation in thirty-nine patients. 2. It has been found that the ligament, when ruptured distally (the most usual type) is often displaced so that the ulnar expansion of the dorsal aponeurosis–here referred to as the adductor aponeurosis–becomes interposed between the ruptured end of the ligament and the site of its attachment on the phalanx; the ligament gets folded over to a greater or lesser extent and the ruptured end sticks out beyond the proximal edge of the adductor aponeurosis. Such displacement of the ligament with interposition of the adductor aponeurosis was found in twenty-five of the thirty-nine cases. The ligament may also be displaced without the adductor aponeurosis being interposed (with a gap between the ruptured end and the site of itsattachment on the phalanx). 3. Variations in the pathological anatomy are illustrated by more detailed descriptions of nine cases. In one of these the adductor aponeurosis had got caught between the two surfaces of the joint, and in another the adductor aponeurosis was found ruptured as well as the ulnar collateral ligament. 4. On the basis of dissection studies on forty-two fresh post-mortem specimens, a rational explanation is given of the pathological anatomy. 5. The results of the present investigation on clinical and anatomical material provide a strong argument in favour of operative treatment for total rupture of the ulnar collateral ligament of the metacarpo-phalangeal joint of the thumb. 6. Aspects of diagnosis and operative technique are discussed