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Medial collateral ligament ruptures in horses are rare and difficult to treat. Conservative treatment usually results in degenerative joint disease that causes permanent lameness. Surgical treatment may be an alternative for salvaging horses for breeding purpose.
We have diagnosed and treated three patients with complete rupture of the radial collateral ligament of the metacarpo-phalangeal joint of the index finger. Rupture of the radial collateral ligament of the metacarpo-phalangeal joint occurs most commonly in the little finger and has not previously been reported in the index finger. Operative treatment is recommended in all cases, due to the significant stresses placed on the radial side of the M.P. joint of the index finger.
The aim of this study was to evaluate the ability of MRI to display injuries of the lateral collateral ligamentous complex in patients with an acute ankle distorsion trauma. The MR examinations of 36 patients with ankle pain after ankle distorsion were evaluated retrospectively without knowledge of clinical history, outcome and/or operative findings. The examinations were performed on a 1. 5-T whole-body imager using a flexible surface coil. The signs for ligamentous abnormality were as follows: complete or partial discontinuity, increased signal within, and irregularity and waviness of the ligament. The results were compared with operative findings in 18 patients with subsequent surgical repair. Eighteen patients with conservative therapy had a follow-up MR examination after 3 months. There was 1 sprain, 3 partial and 32 complete tears of the anterior talofibular ligament, and 5 sprains, 5 partial, and 7 complete tears of the calcaneofibular ligament. There were no lesions of the posterior talofibular ligament. Compared with surgery, MRI demonstrated in 18 of 18 cases the exact extent of anterior talofibular ligament injuries and underestimated the extent in 2 of 8 cases of calcaneofibular ligament injury. In patients with follow-up MRI after conservative therapy, a thickened band-like structure was found along the course of the injured ligament in 17 of 18 cases. The absence of ligament repair after conservative treatment was confirmed during operative revision in one case. The MRI technique allows for grading of the extent of injury of the lateral collateral ligamentous complex after acute ankle strain. It seems to be suitable for monitoring the healing process after conservative-functional treatment of ligament tears.
Cranial transposition of the fibular head stabilizes the stifle joint by displacing the distal attachment of the lateral collateral ligament (LCL). The forces applied to the LCL after displacement may cause ligamentous elongation. This investigation evaluated the morphological, histological, and biomechanical changes of the LCL after fibular head transposition (FHT) in dogs. Unilateral cranial cruciate ligament (CCL) excision and FHT were performed on 25 dogs. Cross-sectional area, length, histological, and structural properties of the LCL were evaluated 3 weeks, 4 months, and 10 months after surgery. Ligament length means were significantly increased at week 3, month 4, and month 10 compared with intraoperative length means. No significant changes in elongation were observed after week 3. Fibrovascular proliferation within the LCL increased the cross-sectional area and associated structural properties.
The viscoelastic properties of the healing medial collateral ligament (MCL) at 12 weeks after isolated injury were investigated in a goat model. The stress-strain relationships, static and cyclic stress-relaxation behaviors of the healing MCL up to 5% strain were determined experimentally using a femur-MCL-tibia complex. These experimental data were used in combination with the quasi-linear viscoelastic (QLV) theory of Fung (1972) to characterize the reduced relaxation function, G(t) (described by constants C, tau1, and tau2) and the elastic response, sigmae(epsilon) (described by constants A and B) of this tissue. It was found that the percentage of stress relaxation for the healing MCLs was significantly greater than those for sham-operated controls (49.0 +/- 12.1% vs. 26.5 +/- 8.1%, respectively; p < 0.05). The product of constants A x B, i.e. the initial slope of the stress-strain curves, was found to be significantly lower for healing MCLs compared to those for sham-operated controls (32.9 +/- 15.8 MPa vs. 118.8 +/- 48.3 MPa; p < 0.05). The dimensionless constant C, i.e. the magnitude of the viscous response, was nearly three times greater for healing MCLs, while constant tau1 was found to be similar between the two groups (0.80 +/- 0.43 s vs. 0.89 +/- 0.52 s, respectively). Constant tau2 for the healing MCL was significantly less than the controls (1269 +/- 38 s vs. 1845 +/- 431 s; p < 0.05) indicating that the stress relaxation reached a plateau earlier. These constants of the QLV theory used to describe the healing MCL were validated for the strain level utilized in this experiment (approximately equal to 4.5%) by predicting the peak stresses during a cyclic stress-relaxation experiment. The theoretically determined values closely matched the experimentally measured values. Thus, this study demonstrates that the QLV theory could be successfully used to describe the viscoelastic behavior of the MCL during the early phases of healing.
Symptomatic calcifications of the rotator cuff tendons is well-known pathologic condition. However, pathologic calcifications may involve other structures of the locomotor system as well. We report about five patients (age 52-66 years) with a painful calcification at the proximal part of the medial collateral ligament of the knee joint. All five patients presented with load-dependent pain pretending meniscus symptoms, but manual valgus stress provoked severe pain at the medial side of the knee. Conventional X-ray examination showed a dense rounded deposit at the proximal part of the medial collateral ligament. Initially all patients were treated conservatively by needling and infiltration with a local anaesthetic. Open resection of the deposit was performed in four patients after unsuccessful conservative treatment. Postoperatively all patients were immediately free of pain. After a mean follow-up of 6 years (patient 1-4) (range=2.5-9.5 years), all patients were still free of pain. Histological evaluation of biopsies obtained during surgery showed nodular deposition of calcium at the collagen fibres, vascular proliferations and inflammative changes. Soft tissue calcifications have to be considered as a rare differential diagnosis in patients presenting with medial knee joint pain. Open resection reduces symptoms immediately. The histological changes seen were comparable to that reported about pathological tendon calcifications of the shoulder. Therefore, both conditions might be of the same aetiology.
BACKGROUND: Studies have suggested that some nonselective nonsteroidal anti-inflammatory drugs, including piroxicam, may improve ligament healing, whereas other nonsteroidal anti-inflammatory drugs, including ibuprofen and the cyclooxygenase-2 inhibitor celecoxib, may have no effect on the mechanical properties or may even deter the healing process. These results might reflect variations in cyclooxygenase enzyme selectivity by different drugs or, alternatively, may be related to their analgesic properties because it is generally accepted that early activity improves ligament healing. HYPOTHESIS: Nonselective nonsteroidal anti-inflammatory drugs improve ligament healing, whereas other analgesics provide lesser degrees of improvement, and cyclooxygenase-2 inhibitors are detrimental. STUDY DESIGN: Controlled laboratory study. METHODS: One hundred fifty-five Sprague-Dawley rats were divided into 7 treatment groups (piroxicam, naproxen, rofecoxib, butorphanol, 2 doses of acetaminophen, and control). The right medial collateral ligament of each rat was transected, and the drugs were administered postoperatively on days 1 to 6. On day 14, the rats were sacrificed, and mechanical testing was performed on the medial collateral ligament. RESULTS: The piroxicam group demonstrated significantly greater load to failure (27%) compared with the control. No significant differences were observed between other groups. CONCLUSIONS: Piroxicam improves ligament healing, but this effect cannot be attributed to all nonselective nonsteroidal anti-inflammatory drugs. Opiate analgesics, acetaminophen, and cyclooxygenase-2 inhibitors do not appear to categorically affect ligament healing. CLINICAL RELEVANCE: In the treatment of ligament injury, piroxicam may be a drug of choice.
Analytical techniques using multiple-exposure roentgenograms were employed to investigate surgical repositioning of either the femoral or the tibial attachment of the medial collateral ligament. The motion of the femoral attachment of the ligament with respect to the tibial attachment was used to compute the changes in length of the borders of the ligament for normal knees and for knees with repositioned attachments. The results support the conclusion that when advancement of the medial collateral ligament is utilized in the treatment of medial instability, optimization is accomplished by distal and anterior advancement with the knee in 30 degrees of flexion. Femoral displacement (proximal realignment) or tibial displacement at knee-flexion angles greater than 45 degrees is not recommended.
One possibility to correct a chronic anteromedial instability of the knee joint is the osseous reinsertion and tightening of the medial collateral ligament. In experiments with a string model and strain gauges attached to the ligaments we investigated the advantages and/or disadvantages of the femoral and tibial reinsertion. Regarding the tension mechanism the medial collateral ligament reacts considerably more sensitivity to the femoral reinsection in proximal-dorsal direction than to the tibial-reinsertion in distal-ventral direction. An accurate knee flexion between 40 and 60 degrees has to be provided reinserting the ligament in proximal-dorsal direction to avoid excessive tension and resulting destruction of the ligament. However the reinsertion of the ligament in distal-ventral direction, independently from the flexion of the knee, always approximates the natural tension of the anterior and posterior margin of the untreated ligament. Biomechanically the reinsertion in distal-ventral direction to tighten the loose ligament seems to be preferable to the reinsertion in proximal-dorsal direction.
The ability of ultrasound to assess a displaced ulnar collateral ligament of the 1st metacarpo-phalangeal (MCP) joint was evaluated. If the ligament is ruptured and displaced proximal to the adductor aponeurosis, a surgical repair should be undertaken to restore stability. Ultrasound accurately diagnosed these lesions in 32/39 operated patients. In 4 cases the ultrasound examination suggested a more severe lesion than was found at operation. In 3 cases a lesser injury was suspected than later proved to be present.
Ligaments are subjected to a range of loads during different activities in vivo, suggesting that they must resist creep at various stresses. Cyclic and static creep tests of rabbit medial collateral ligament were used as a model to examine creep over a range of stresses in the toe- and linear-regions of the stress-strain curve: 4.1 MPa (n = 7), 7.1 MPa (n = 6), 14 MPa (n = 9) and 28 MPa (n = 6). We quantified ligament creep behaviour to determine if, at low stresses, modulus would increase in a cyclic creep test and collagen fibres would be recruited in a static creep test. At higher creep stresses, a decrease in measured modulus was expected to be a potential marker of damage. The increase in modulus during cyclic creep and the increase in strain during static creep were similar between the three toe-region stresses (4.1, 7.1, 14 MPa). However, at the linear-region stress (28 MPa), both these parameters increased significantly compared to the increases at the three toe-region stresses. A concurrent crimp analysis revealed that collagen fibres were recruited during creep, evidenced by decreased area of crimped fibres at the end of the static creep test. Interestingly, a predominance of straightened fibres was observed at the end of the 28 MPa creep test, suggesting a limited potential for fibre recruitment at higher, linear-region stresses. An additional 28 MPa (n = 6) group had mechanically detectable discontinuities in their stress-strain curves during creep that were related to reductions in modulus and suggested fibre damage. These data support the concept that collagen fibre recruitment is a mechanism by which ligaments resist creep at low stresses. At a higher creep stress, which was still only about a third of the failure capacity, damage to some ligaments occurred and was marked by a sudden reduction in modulus. In the cyclic tests, with continued cycling, the modulus increased back to original values obtained before the discontinuity suggesting that other fibres were being recruited to bear load. These results have important implications for our understanding of how fibre recruitment and stress redistribution act in normal ligament to minimize creep and restore modulus after fibre damage.
The strain distribution over the entire medial collateral ligament (MCL) was measured using a photoelastic coating method. This new approach utilized a polyurethane monomer as a photoelastic coating film. The initial experiments investigating MCL strain measurement showed that this film had a high sensitivity for strain and good adhesion to the ligament. It was confirmed that strain distribution could be obtained qualitatively over the entire ligament using this method. The mechanism of MCL injury was studied by applying this polyurethane coating film to the entire MCL in a femur-MCL-tibia complex. When simple tension was applied to the complex, strain concentrations were centred at the tibial insertion site, and all the specimens ruptured at the MCL tibial insertion site. With application of a valgus bending moment, increased strain was seen in the MCL from the medial femoral condyle to the medial epicondyle. Histological analysis demonstrated midsubstance ligament ruptures in this same region. For both tests, rupture sites and increased strain concentration sites correlated. In addition, an impingement phenomenon of the MCL on the medial femoral condyle can be seen during application of valgus force, and this phenomenon may explain the higher incidence of MCL injuries on the femoral side seen in the clinical setting. This polyurethane coating method allows for direct and visual measurements, and can qualitatively measure the strain behaviour over the entire MCL surface. This new technique represents a significant improvement over previous point-by-point strain measurement methods.
This paper describes the anatomy of the lateral collateral ligament (LCL). The dimensions of the ligament and its femoral and fibular attachments are given. The relationships between the LCL and other anatomical structures are described, particularly the terminal fiber branches of the biceps femoris. The histological features of the ligament fibers and their osseous attachments are also described.
On 34 osteoligamentous ankle preparations the function of the various components of the deltoid ligament has been elucidated by tracing mobility patterns after successive transection of the components in varying sequence. The anterior and posterior talofibular ligaments were included in the study to investigate the interaction between these structures and the deltoid ligament. The tibiocalcaneal and the intermediate tibiotalar ligaments control abduction of the talus. The anterior tibiotalar and talofibular ligaments control plantar flexion, while dorsiflexion is inhibited by the posterior tibiotalar and talofibular ligaments, and partly by the anterior talofibular ligament as well. In combination, the anterior and intermediate tibiotalar ligaments control external rotation, while the intermediate and posterior tibiotalar ligaments control both external and, together with the anterior talofibular ligament, internal rotation of the talus. Isolated, neither the anterior nor the posterior tibiotalar ligament appears to play any major role in ankle stability.
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AIM: To study the long term result of open reduction of longstanding dislocated elbows with regard to stability, avascular necrosis of the distal humerus and degenerative changes of the joint. METHODS: Nine patients, aged between nine and 60 years (average 30 years) with longstanding posterior dislocation of the elbow underwent open reduction. The operative procedure featured a medial and lateral incision, excision of the capsule, fibrous adhesions and the collateral ligaments with no attempt to reconstruct the ligaments, as well as anterior transposition of the ulnar nerve. The procedure was performed on an average eight months after the injury (range 1.5 to 30 months). RESULTS: All elbows had improved flexion at follow-up which ranged from one to eleven-and-half years (average 48 months). The average arc of flexion improved from 11 degrees to 87 degrees. The average flexion at the elbow improved from 32 degrees (range 20 degrees - 50 degrees ) to 111 degrees (range 85 degrees - 140 degrees ). Younger patients with fractures of the articular surface of distal humerus had smaller gain in the range of motion. No patient complained of instability or had recurrence of dislocation. No patient developed avascular necrosis of the distal end of the humerus. The radiographs of the 60-year-old man at 11.5 years follow-up showed extensive degenerative changes of the joint but he still maintained a painless arc of flexion from 10 degrees to 135 degrees. CONCLUSION: There was improvement in the range of motion and function in all nine patients. The elbows were stable despite excision of the collateral ligaments. There was no evidence of avascular necrosis. Patients with eight or more years of follow-up showed degenerative changes of the joint.
To determine if small avulsion fractures of the thumb ulnar collateral ligament (UCL) with minimal (< or = 2.0 mm) displacement can successfully be treated by cast immobilization, the authors reviewed 9 patients with minimally displaced fractures initially treated by casting. Despite immobilization within an average of 2 days of the initial injury (range, 0-6 days), a minimum of 6 weeks of immobilization in a cast, and adequate rehabilitation, all 9 patients had persistent thumb pain, especially with activities requiring strong pinch. After undergoing open reduction and internal fixation, the patients had relief of thumb pain and pinch strength improved from 36% of the contralateral side to 89% (p < .01). Grip strength increased from 77% to 93% (p < .05), but the ranges of motion of the thumb metacarpophalangeal and interphalangeal joints were not significantly altered. Minimally displaced UCL avulsion fractures frequently have significant rotation that prevents successful fracture healing even with prompt cast immobilization.
The anatomy of the lateral ulnar collateral ligament (LUCL) of the elbow was investigated in 26 fresh frozen cadavers. Two types of insertion of the LUCL were originally described but we found another type which is characterized by a broad single expansion along with a thin membranous fibre. Strain on the LUCL was measured in situ during extension and flexion with the forearm in supination, pronation and neutral. Strain in the proximal fibres started to occur at around 32 degrees flexion and peaked at between 50 degrees and 60 degrees flexion. Strains measured in the distal fibres were smaller in magnitude. Forearm rotation had little effect on strain during extension to flexion. Based on these results, we conclude that the LUCL functions in unison with the annular ligament.