Evaluation of the Intact Anterior Talofibular and Calcaneofibular Ligaments, Injuries, and Repairs With and Without Augmentation: A Biomechanical Robotic Study.

BACKGROUND: Acute ankle sprains are common injuries. The anterior talofibular (ATFL) and calcaneofibular ligaments (CFL) are the most injured lateral structures. However, controversy exists on the optimal surgical treatment when the injury is both acute and severe or becomes chronic and unstable. Studies have evaluated the biomechanics of these ligaments, but no studies have robotically evaluated injury effects and surgical treatment of ATFL or ATFL and CFL injuries. PURPOSE: To quantitatively evaluate biomechanical effects of ATFL and CFL lesions, ATFL repair, ATFL and CFL repair, and augmentation of ATFL on ankle stability. STUDY DESIGN: Controlled laboratory study. METHODS: Ten nonpaired cadaveric ankles were tested using a 6 degrees of freedom robot. Each ankle underwent testing in the following states sequentially: (1) intact, (2) ATFL cut, (3) CFL cut, (4) ATFL repair + CFL cut, (5) ATFL repair + CFL repair, and (6) ATFL repair with augmentation with suture tape + CFL repair. Testing included 88 N anterior drawer and 5 N·m varus talar tilt tests at 0° and 30° of plantarflexion, and 88 N Cotton test at 0° of plantarflexion. RESULTS: After all surgical treatments ankles still had increased laxity compared with intact state testing, except after augmented ATFL repair + CFL repair in anterior drawer testing at 30° of plantarflexion (P = .393). Sectioning the CFL caused a significant increase in talar tilt compared with the ATFL cut state at 0° (P < .001) and 30° of plantarflexion (P < .001), but no increase in anterior drawer or Cotton tests. CONCLUSION: Complete native stability may not be attainable at time zero repair with the tested treatments. The option that best returned stability in anterior translation was augmented ATFL repair with nonaugmented CFL repair. The importance of the CFL as a primary ligamentous stabilizer for talar tilt was confirmed. CLINICAL RELEVANCE: Evaluating lateral ankle stability and treatment with a 6 degrees of freedom robot should help delineate optimal treatment options. Findings in this study show that none of the repair methods at time zero restored kinematics to the intact state. Of the tested states, the augmented ATFL repair with CFL repair was the best option for controlling anterior translation at time zero. The importance of addressing the CFL to correct talar tilt instability was suggested as was the importance of a period of immobilization before beginning protected rehabilitation. The benefit of ATFL repair augmentation with suture tape is in limiting the postoperative motion in an anterior drawer motion to just 0.5 to 1 mm, but there was no significant improvement to talar tilt even with CFL repair, suggesting that further consideration should be given to CFL augmentation in future studies.

Locked Dorsal Compression Plate Arthrodesis for Degenerative Arthritis of the Midfoot.

Midfoot arthrodesis is the accepted surgical treatment for symptomatic midfoot arthritis. The published literature has focused on joint-spanning static fixation. Several companies have developed diamond-shaped locked dorsal compression plates, which allow for longitudinal joint compression. After dorsal plate insertion, a spreader device opens the arms of the plate mediolaterally, which allows the plate to compress longitudinally. This work describes outcomes of such locked dorsal compression plates for midfoot arthritis at a single institution. We reviewed 62 patients who underwent midfoot arthrodesis for symptomatic midfoot arthritis using locked dorsal compression plates over a 7-year period. A total of 173 joints were spanned for fusion. The primary outcome measure was radiographic union and visual analog scale pain scores. Characteristics of patients who experienced nonunion versus those who had union were evaluated. Of the 173 joints, there was a 81.5% fusion rate (141/173 joints) and 14 patients experienced nonunion. There was a statistically significant difference in the average number of joints spanned in patients with nonunion (3.6) and patients with union (2.5) (p = .02). Locked dorsal compression plate arthrodesis is a viable technique for achieving midfoot fusion. This mechanical method of compression does not, however, lend itself to improved fusion rates compared with prior reports. A greater number of arthrodesis sites is associated with a higher nonunion rate. Emerging technology using newer materials and improved biomechanical designs may show improved results.

Comparison of Single-Agent Versus 3-Additive Regional Anesthesia for Foot and Ankle Surgery.

BACKGROUND: This study compared the results of regional blocks containing a single anesthetic, bupivacaine, with those containing bupivacaine and 3 additives (buprenorphine, clonidine, and dexamethasone) in patients undergoing foot and ankle surgery. METHODS: Eighty patients undergoing foot and ankle surgery over a 9-month period were prospectively enrolled and randomized to receive a peripheral nerve block containing either a single anesthetic (SA) or one with 3 additives (TA). Patients, surgeons, and anesthesiologists were blinded to the groups. Patients maintained pain diaries and were evaluated at 1 and 12 weeks postoperatively. Fifty-six patients completed the study. RESULTS: The TA group had a longer duration of analgesic effect than the SA group (average 82 vs 34 hours, P < .05). Forty-eight hours after surgery, 93% of SA blocks, compared with 34% of TA blocks, had completely worn off. The TA group had a longer duration of sensory effects. At 3 months, 10 of 26 (38.5%) TA patients, compared with 3 of 30 (10%) SA patients, reported postoperative neurologic symptoms. Pain scores in both groups were not statistically different at 1 week or 3 months after surgery. Patients in both groups were similarly satisfied with their blocks. CONCLUSION: Both types of nerve blocks provided equivalent pain control and patient satisfaction in patients undergoing foot and ankle surgery. The 3-additive agent blocks were associated with a longer duration of pain relief and a longer duration of numbness, as well as higher rates of postoperative neurologic symptoms. Longer pain relief may be obtained at the cost of prolonged sensory deficits. LEVEL OF EVIDENCE: Level II, prospective comparative study.

Cognition following computer-assisted total knee arthroplasty: a prospective cohort study.

BACKGROUND: A substantial number of patients experience postoperative cognitive changes following total joint arthroplasty. The change in mental status may be the result of fat and bone-marrow-debris embolization. We hypothesized that the use of computer-assisted total knee arthroplasty, which does not involve the use of intramedullary alignment rods, would produce less fat and bone-marrow-debris embolization and, hence, fewer changes in mental status. METHODS: Forty-seven patients who underwent total knee arthroplasty with use of a computer-assisted navigation system and forty-eight patients who underwent conventional total knee arthroplasty without the assistance of computer navigation were followed prospectively. The validated Folstein Mini-Mental State Examination (MMSE) was used to assess the mental status of the patients. The test was administered preoperatively, serially postoperatively while the patient was in the hospital, and at six months. Medication and oxygen requirements were recorded. RESULTS: On the basis of the numbers studied, no significant differences in postoperative pain-medication or oxygen requirements were found between the group treated with computer-assisted navigation (the navigation group) and the group treated with conventional total knee arthroplasty (the control group). The mean postoperative MMSE score was 88.9 points in the navigation group and 89.3 points in the control group (p = 0.844). Twenty-five patients in the navigation group and thirty-six patients in the control group completed the test at six months. The mean score at that time was 95.3 points in the navigation group and 96.3 points in the control group (p = 0.514). CONCLUSIONS: Further research is needed to determine if fat and bone-marrow-debris embolization is truly decreased by the use of computer-assisted total knee arthroplasty and if such a reduction has any clinical relevance.