Beat Hintermann

Ligamentous posttraumatic ankle osteoarthritis

Background Ankle sprains are the most common injuries in sports and recreational activities. Hypothesis Ankle osteoarthritis can be caused by ankle ligament lesions. Latency time between injury and osteoarthritis is influenced by the type and side of the injured ligaments. The side of the ligamentous lesion correlates with the hindfoot alignment. Study Design Case series; Level of evidence, 4. Methods Of a cohort of 247 patients with ankle arthritis, we reviewed data from 30 patients (33 ankles; mean age, 58.6 years) with ligamentous end-stage ankle osteoarthritis. The patients were evaluated etiologically, clinically, and radiologically. Results Etiologic analysis: 55% had a ligamentous lesion from sports injuries (soccer, 33%); 85% injured the lateral ankle ligaments, and 15% injured the medial and medial-lateral ligaments. The mean latency time between injury and osteoarthritis was 34.3 years. The survivorship rate for single severe ankle sprains was worse than that for chronic recurrent ligamentous lesions (mean latency time, 25.7 vs 38.0 years; P< .05), and the rate for medial sprains was worse than for lateral sprains (mean latency time, 27.5 vs 35.0 years; P< .05). At follow-up, the American Orthopaedic Foot and Ankle Society hindfoot score was 23.0 points, 52% had varus malalignment, 52% had persistent instability, and the mean ankle arthritis grade was 2.6 points. There was a correlation between chronic lateral ankle instability and varus malalignment. Conclusion Lateral ankle sprains in sports are the main cause of ligamentous posttraumatic ankle osteoarthritis and correlate with varus malalignment. At the time of end-stage ligamentous ankle osteoarthritis, persistent instability may be encountered.

Arthroscopic Findings in Patients with Chronic Ankle Instability

Background There are little objective data on structural changes of the chronically unstable ankle. Such knowledge could help with preoperative planning. Hypothesis Preoperative ankle arthroscopy provides important insights into the causes and mechanisms of ankle instability and the resulting disability. Study Design Case series. Methods From 1993 to 1999, arthroscopic examination was performed in the ankles of 148 patients with symptomatic chronic ankle instability that had lasted 6 months or more. All structural changes were recorded and compared with the clinical diagnosis. Results A rupture or elongation of the anterior talofibular ligament was noted in 86% of ankles, of the calcaneofibular ligament in 64%, and of the deltoid ligament in 40%. Cartilage damage was noted in 66% of ankles with lateral ligament injuries, whereas 98% of the ankles with deltoid ligament injuries had cartilage damage. Although lateral instability could be verified arthroscopically in 127 patients, medial instability was presumed clinically in 38 patients but was actually detected in 54 patients arthroscopically. Conclusion Preoperative ankle arthroscopy revealed an essential amount of information that would otherwise have been undetected. For instance, the ligaments showed typical abnormalities corresponding to different entities of ankle instability and different intra-articular pathologic conditions.

Realignment surgery as alternative treatment of varus and valgus ankle osteoarthritis.

In patients with asymmetric (varus or valgus) ankle osteoarthritis, realignment surgery is an alternative treatment to fusion or total ankle replacement in selected cases. To determine whether realignment surgery in asymmetric ankle osteoarthritis relieved pain and improved function, we clinically and radiographically followed 35 consecutive patients with posttraumatic ankle osteoarthritis treated with lower leg and hindfoot realignment surgery. We further questioned if outcome correlated with achieved alignment. The average patient age was 43 years (range, 26-68 years). We used a standardized clinical and radiographic protocol. Besides distal tibial osteotomies, additional bony and soft tissue procedures were performed in 32 patients (91%). At mean followup of 5 years (range, 3-10.5 years), pain decreased by an average of 4 points on a visual analog scale; range of ankle motion increased by an average of 5°. Walking ability and the functional parts of the American Foot and Ankle Society score increased by an average of 10 and 21 points, respectively, and correlated with achieved reversal of tibiotalar tilt and the score of Takakura et al. Revision surgery was performed in 10 ankles (29%), of which three ankles (9%) were converted to total ankle replacement. We believe the data support realignment surgery for patients with asymmetric ankle osteoarthritis. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Lengthening of the Lateral Column and Reconstruction of the Medial Soft Tissue for Treatment of Acquired Flatfoot Deformity Associated with Insufficiency of the Posterior Tibial Tendon

We analyzed our results of surgery for acquired flatfoot deformity after dysfunction of the posterior tibial tendon. This included lengthening the proximal lateral column by calcaneal osteotomy and reconstructing the medial soft tissue. Nineteen patients (9 women and 10 men; average age, 52.9 years [range, 24–72 years]) were treated for stage II and stage II–III insufficiency of the posterior tibial tendon. The medial soft tissue surgery included 18 reconstructions of the tendon, 11 transfers of the flexor digitorum longus tendon, 13 repairs of the deltoid ligament, and 3 repairs of the spring ligament. At follow-up (mean, 23.4 months), all patients had satisfactory restoration of their medial longitudinal arch, reduction of abduction in the forefoot, and restored height in the arch. All patients were able to bear weight fully on the foot that underwent surgery, and all but one were satisfied with the result achieved. The clinical result was rated as excellent in 6, good in 11, and fair in 2 cases. In all but one case, no loss of achieved correction in the foot was found. In one case, the calcaneocuboid joint had to undergo arthrodesis after 5 months because of painful degenerative joint disease. In the pes planovalgus and abductus deformities occurring in stage II disease, calcaneal osteotomy and reconstruction of the medial tendon and ligament seem to play a significant role in operative management. This was the case only when degenerative joint disease and significant subluxation of the subtalar or talonavicular joint or both had not already occurred. They seem to function by restoring more normal biomechanics, which allows reconstructed or transferred tendon to function successfully.

Rigid internal fixation of fractures of the proximal humerus in older patients

In 42 elderly patients, 33 women and nine men with a mean age of 72 years, we treated displaced fractures of the proximal humerus (34 three-part, 8 four-part) using a blade plate and a standard deltopectoral approach. Functional treatment was started immediately after surgery. We reviewed 41 patients at one year and 38 at final follow-up at 3.4 years (2.4 to 4.5). At the final review, all the fractures had healed. The clinical results were graded as excellent in 13 patients, good in 17, fair in seven, and poor in one. The median Constant score was 73 +/- 18. Avascular necrosis of the humeral head occurred in two patients (5%). We conclude that rigid fixation of displaced fractures of the proximal humerus with a blade plate in the elderly patient provides sufficient primary stability to allow early functional treatment. The incidence of avascular necrosis and nonunion was low. Restoration of the anatomy and biomechanics may contribute to a good functional outcome when compared with alternative methods of fixation or conservative treatment. Regardless of the age of the patients, we advocate primary open reduction and rigid internal fixation of three- and four-part fractures of the proximal humerus.

Arthroscopic Findings After Shoulder Dislocation

The purpose of this study was to evaluate prospectively the arthroscopic findings of the unstable shoulder, to provide insights into the causes and mechanisms of shoulder instability, and to establish a rationale for using special surgical procedures. Arthroscopic examination was performed on 212 patients who had at least 1 docu mented shoulder dislocation. Of these 212 patients, 184 (87%) patients had anterior glenoid labral tears, 168 (79%) patients had ventral capsule insufficiency, 144 (68%) patients had Hill-Sachs compression fractures, 116 (55%) patients had glenohumeral ligament insuf ficiency, 30 (14%) patients had complete rotator cuff tendon tears, 26 (12%) patients had posterior glenoid labral tears, 14 (7%) patients had superior labrum an terior and inferior lesions. As this prospective study shows, multiple morphologic changes are associated with instability of the glenohumeral joint; there is no single cause for an unstable shoulder. Arthroscopic ex amination of the shoulder before surgery revealed a sig nificant amount of information that would have been un detected without the aid of expensive diagnostic tools. For instance, the labrum and rim of the anteroinferior glenoid showed typical abnormalities corresponding to different entities of anterior instability.

New trends in the treatment of proximal humerus fractures.

For complex proximal humeral fractures, most authors agree on the importance of anatomic reduction and stable fixation to allow early range of motion. Currently a variety of techniques are used such as K-wires, t-plates, and primary prosthesis among others. However, no current treatment guidelines have been established. Newer implants provide greater angular stability, better biomechanical properties, and enhanced anchorage in these complex injuries. These implants therefore have a potential for achieving better results in treating complex fractures. We discuss current treatment concepts and focus on biomechanics and early results of new implants designed to provide angular stability.Level of Evidence: Expert Opinion, Level V. See the Guidelines for Authors for a complete description of levels of evidence.

Arthroscopic findings in acute fractures of the ankle

We have evaluated prospectively the arthroscopic findings in acute fractures of the ankle in 288 consecutive patients (148 men and 140 women) with a mean age of 45.6 years. According to the AO-Danis-Weber classification there were 14 type-A fractures, 198 type B and 76 type C. Lesions of the cartilage were found in 228 ankles (79.2%), more often on the talus (69.4%) than on the distal tibia (45.8%), the fibula (45.1%), or the medial malleolus (41.3%). There were more lesions in men than in women and in general they were more severe in men (p < 0.05). They also tended to be worse in patients under 30 years and in those over 60 years of age. The frequency and severity of the lesions increased from type-B to type-C fractures (p < 0.05). Within each type of fracture the lesions increased from subgroups 1 to 3 (p < 0.05). The anterior tibiofibular ligament was injured with increased frequency from type-B.1 to type-C3 fractures (p < 0.05), but it was not torn in all cases. While lateral ligamentous injuries were seen more often in type-B than in type-C fractures (p < 0.05), no difference was noted in the frequency of deltoid ligamentous lesions. Our findings show that arthroscopy is useful in identifying associated intra-articular lesions in acute fractures of the ankle.

Pronation in runners. Implications for injuries.

In spite of some significant progress in the understanding of the biomechanics of the ankle joint complex, especially the coupling mechanism between foot and leg, various mechanisms causing overuse injuries in the lower extremities are still poorly understood. Some increased pronation of the foot is often physiological, but excessive pronation is potentially harmful. Compensatory overpronation may occur for anatomical reasons. However, not only the amount of foot eversion, but also the way this eversion is transferred into tibial rotation may be crucial to the overloading stress on the knee. In other words, the individual transfer mechanism of foot eversion into internal tibial rotation may be of some predictable value for lower extremity overloading and related injuries.Further research is necessary to improve the functional understanding of anatomical and biomechanical abnormalities and their pathological value in predicting overuse injuries.

Kinematic Changes After Fusion and Total Replacement of the Ankle Part 1: Range of Motion

Background: The purpose of this study was to determine how closely the present designs of ankle prostheses mimic the unique requirements of the foot and ankle. The three-dimensional range of motion (ROM) of the ankle joint complex, before and after ankle arthrodesis and after implantation of three currently used total ankle prostheses, was investigated. Methods: The three-dimensional ROM was determined in six fresh-frozen cadaver leg specimens using a 6-df device with an axial load of 200 N and a four-camera high-speed video system. A moment of 100 Nm was applied to the footplate to determine the ROM in the sagittal (dorsiflexion and plantarflexion) and frontal (inversion and eversion) planes. The same moment was applied to the tibia to determine the ROM for the internal and external tibial rotation. The measurements were performed for the normal ankle, the fused ankle, and the AGILITY, HINTEGRA, and S.T.A.R. prostheses. Results: Compared to the normal condition, the ROM for dorsiflexion and plantarflexion was changed for all surgical interventions. The changes were highest for the ankle arthrodesis. The changes due to the prostheses were significantly less than the changes due to ankle arthrodesis. Compared to the normal condition, the total ROM for inversion/eversion was slightly decreased by the fused ankle and not changed by the three-component prostheses (HINTEGRA, S.T.A.R.). However, the ROM for inversion/eversion was significantly higher for the two-component prosthesis, AGILITY. The ROM for internal and external tibial rotation was not altered by the AGILITY and HINTEGRA ankle, but it was significantly reduced by the ankle arthrodesis. S.T.A.R. showed a significant shift of the total ROM toward internal tibial rotation. Conclusions: The three tested ankle joint prostheses changed the ROM of the ankle joint complex less than ankle fusion did. Total ankle prostheses were shown to replicate normal joint ROM closely. However, ankle arthrodesis was found to reduce the ROM substantially in all three planes: the sagittal, frontal, and horizontal planes. Clinical Implications: With respect to the ROM, total ankle replacement changes the natural ankle joint condition less than ankle arthrodesis, which reduces the ROM in all three planes and might increase stress in adjacent structures. The prosthesis that replicated the normal ankle joint ROM best was the one with the most anatomical design.