Evaluating Prospective Patient-Reported Pain and Function Outcomes After Ankle and Hindfoot Arthrodesis

Background: Hindfoot and ankle fusions are mechanically limiting procedures for patients. However, patient-reported outcomes of these procedures have not been well studied. This study assessed outcomes of hindfoot and ankle fusions by using Patient-Reported Outcome Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference (PI) Computer Adaptive Tests (CATs). Methods: Between 2014 and 2018, 102 patients were prospectively enrolled after presenting to a tertiary care facility for ankle and hindfoot fusions, including tibiotalar, tibiotalocalcaneal, subtalar, and triple arthrodeses. Study participants completed preoperative and 12-month postoperative PF and PI CATs. The differences between mean 12-month postoperative and preoperative PROMIS PF and PI T scores were analyzed with paired t tests. The relationship between the 12-month PF and PI differences for the overall sample and patient factors was examined using multiple regression modeling. Results: The sample had mean age of 57.69 years; 48% were male, and 55% were obese. Patients who underwent ankle and hindfoot arthrodesis had statistically significant improvements from preoperative to 12 months postoperative in mean PF (36.26±7.85 vs 39.38±6.46, P = .03) and PI (61.07±7.75 vs 56.62±9.81, P = .02). Triple arthrodesis saw the greatest increases in physical function (▵PF = 7.22±7.31, P = .01) and reductions in pain (▵PI = –9.17±8.31, P = .01), achieving minimal clinically important difference (MCID). Patients who underwent tibiotalar fusion had significant improvement in physical function (▵PF = 4.18±5.68, P = .04) and pain reduction that approached statistical significance (▵PI = –6.24±8.50, P = .09), achieving MCID. Older age (≥60 years ) was associated with greater improvements in PF ( β = 0.20, P = .07) and PI ( β = –0.29, P = .04). Preoperative PF and PI T scores were significantly associated with the 12-month change in PF and PI T scores, respectively ( β = –0.74, P < .01; β = –0.61, P < .01). Conclusion: Hindfoot and ankle fusions are procedures with favorable patient outcomes leading to increased physical function and decreased pain at 12 months postoperation relative to preoperation. Level of Evidence: Level II, prospective comparative study.

Outcome of Pantalar Fusion With Femoral Head Allograft in Avascular Necrosis of Talus

Background: Avascular necrosis (AVN) of the talus is a challenging condition that is caused primarily by trauma. The severity of the talus fracture determines the risk of AVN. Severe osteonecrosis with the loss of talar integrity can be treated with arthrodesis and structural bone graft.Method: This study shows the experience of pantalar arthrodesis using hindfoot arthrodesis nail, screw fixation, and femoral head allograft in four patients.Result: All patients were satisfied in terms of pain and function after an average of 4 months postsurgery. Limb length discrepancy was &lt;1 cm and hindfoot fusion was achieved by 3 months. The mean score for SF-36 physical function and AOFAS hindfoot score at a 2-year postpantalar arthrodesis was 88 and 80.8, respectively.Conclusion: Hindfoot ankle arthrodesis, with the usage of femoral head allograft, can be successfully used for the treatment of traumatic AVN of talus.

Single Medial vs 2-Incision Approach for Double Hindfoot Arthrodesis: Is There a Difference in Joint Preparation?

Background: Double hindfoot arthrodesis is a reliable treatment option in lower extremity deformity and arthritis. Single (medial) and 2-incision techniques have been described. The purpose of this study was to evaluate the extent of cartilage debrided in each approach and to evaluate the competency of the deltoid ligament. Methods: Eight matched pairs of cadaveric specimens were acquired. One limb from each pair was randomly assigned to the single medial incision and the other to the 2-incision technique. Stress radiographs were obtained prior to dissection to evaluate for valgus tibiotalar tilt. The talonavicular and subtalar articular surfaces were denuded of cartilage and the joints disarticulated. The percentage of cartilage debrided was determined using ImageJ software. Postoperative tibiotalar tilt was measured with a technique and threshold previously described by our group. The intraclass correlation coefficient was calculated to determine inter- and intraobserver reliability. Results: The single medial incision demonstrated significantly less cartilage denuded than the 2-incision technique at the talar head (61.1% ± 20.4% vs 88.1% ± 6.1%, P < .001), and the posterior facets of the talus (53.5% ± 7.6% vs 73.6% ± 7.0%, P < .001) and calcaneus (55.3% ± 16.5% vs 81.0% ± 7.4%, P = .001). Overall, 75% of specimens that underwent a single medial incision approach demonstrated increased valgus tibiotalar tilt postdissection, whereas none that underwent the 2-incision technique developed increased tibiotalar tilt ( P < .01). The average tibiotalar tilt among these specimens was 4.6 ± 1.3 degrees (range 2.5-5.7 degrees). For all measurements, the intraclass correlation coefficient was greater than 0.8. Conclusion: The posterior facet of the subtalar joint and talar head are at risk of subtotal debridement, as well as increased tibiotalar tilt with the single medial incision technique. Adequate debridement may require greater soft tissue dissection, possibly at the expense of medial ankle stability. Level of Evidence: Level III, retrospective cohort study.

Mechanical Effects of Lag Screw Retightening in a Simulated Hindfoot Arthrodesis Model

Background: Nonunion following hindfoot arthrodesis may be caused by failure to maintain compression at the arthrodesis site. The ability of lag screws, commonly used in arthrodesis, to maintain compression in hindfoot bones has not been well characterized. The aim of this work was to quantify the stress relaxation response of hindfoot bone with initial and repeated compression with a lag screw. Methods: Ten sets of 25-mm-diameter bone cylinders were cut from the talus and calcaneus in fresh-thawed cadaveric feet. A load cell was compressed between cylinders with an 8.0-mm partially threaded cannulated lag screw simulating arthrodesis. For 7 sets, screws were tightened by 3 quarter-turns, rested for 3 minutes, retightened 1 quarter-turn, and rested for 30 minutes. Three sets served as controls in which screws were not retightened. Results: Maximum compression after initial screw tightening and retightening averaged 275 and 337 N ( P = .07), respectively. Compression 3 minutes after initial screw tightening and retightening averaged 199 and 278 N ( P = .027), respectively. The compression recorded 3 minutes after screw retightening was an average of 40% higher than that recorded 3 minutes after initial tightening. The average compression 30 minutes after screw retightening was 255 N, a compression loss of 25% from the average maximum compression after retightening. Eighty percent of this compression loss happened in an average of 5.5 minutes. Conclusion: Hindfoot bones exhibit compression loss over time during simulated arthrodesis. Compression maintenance in bone is improved with screw retightening. Further work is needed to understand the mechanism of action and determine optimum time for recompression. Clinical Relevance: Retightening lag screws before wound closure may improve compression at the arthrodesis site and thereby decrease the chance of nonunion. Level of Evidence: N/A, laboratory experiment.

Local Ketorolac Injection vs Popliteal Sciatic Nerve Blockade as an Adjuvant to a Spinal Block in Hindfoot Arthrodesis

Background: Popliteal nerve blocks reduce pain and markedly improve postoperative outcomes during foot and ankle surgery; however, several potential complications may arise from nerve block procedures. The purpose of this study was to investigate local infiltration analgesia with ketorolac as a convenient alternative for pain relief. Methods: A total of 80 patients scheduled for hindfoot arthrodesis were randomly allocated to one of 2 anesthetic groups: a spinal block augmented with either a popliteal nerve block (n = 40) or local ketorolac and Marcaine infiltration (n = 40). Clinical assessment included postoperative visual analog scale (VAS) pain scores at 4, 8, 12, 24, and 48 hours, total morphine consumption, time to incision (time in operating room to incision), operative time, length of hospital stay, and complications. Results: Despite similar morphine consumption between groups ( P = .28), VAS scores were significantly lower at 24 hours (1.6 ± 2.2 cm vs 2.7 ± 3.0 cm, P = .01) and 48 hours (0.2 ± 0.7 cm vs 1.0 ± 1.5 cm, P < .01) after surgery using local ketorolac injection. Although time from entry into the operating room to incision was also reduced after local ketorolac injection (19.0 ± 5.3 minutes vs 31.4 ± 14.6 minutes, P < .001), the length of operative time ( P = .38), hospital stay ( P = .43), and number of complications ( P = .24) were similar between groups. Conclusion: Ketorolac local injection provided effective pain control in hindfoot arthrodesis and markedly reduced VAS pain scores up to 48 hours after surgery compared with popliteal nerve block. In addition, ketorolac local injection also reduced time in the operating room compared with popliteal nerve blockade. Level of Evidence: Level 1, randomized controlled trial.

Does Lag Screw Retightening Improve Compression in Hindfoot Arthrodesis?

Category: Hindfoot; Ankle; Ankle Arthritis Introduction/Purpose: Non-union and delayed union are common complications following hindfoot arthrodesis. The failure to obtain and maintain compression at the arthrodesis site may be a causative factor. Partially threaded cannulated ‘lag’ screws are commonly used for fixation in hindfoot arthrodesis; however, the ability of these screws to maintain compression in the hindfoot bones has not been well-characterized. The goals of this work were to: 1) quantify the stress relaxation response of hindfoot bones when compressed with a lag screw, particularly compression change upon screw retightening, and 2) compare the results to prior studies on stress relaxation in direct bone compression. Methods: 12 pairs of calcaneus, talus and tibia bone cylinders, 25mm in diameter, were cut with a keyhole saw from fresh thawed cadaveric feet. The bone cylinders were prepared for simulated arthrodesis by removing the cartilage and flattening the subchondral surface with an oscillating saw. A Futek LTH 300 donut load cell and two metal washers were sandwiched between the two bone cylinders. An 8.0mm partially threaded cannulated lag screw (Smith and Nephew) was placed from the posterior- inferior aspect of the calcaneus cylinder to the anterior-superior aspect of the talus cylinder to simulate subtalar arthrodesis, or from the superior aspect of the tibia cylinder to the inferior aspect of the talus cylinder. Compression was recorded continuously as the screws were tightened by three-quarters of a turn and left untouched for 3 minutes. Recording continued as the screws were retightened one quarter-turn and then left untouched for 30 additional minutes. Results: Both initial and subsequent compression with a lag screw demonstrated a stress relaxation pattern, with increased maximum compression and slowed decay upon retightening. Maximum compression after three quarter-turns and retightening averaged 284 N and 351 N, respectively (n=12; t=-2.55; p=0.0136). Time to decay to 80% of maximum compression after three quarter-turns and retightening averaged 34 and 528 (n=9; t=-2.59; p=0.0159) seconds, respectively, compared to 21 seconds for direct compression. Compression loss 30 minutes after retightening averaged 25.5% (SD=8.8%), compared to 34.3% for direct compression. Conclusion: The maximum compression attained following retightening was significantly greater than the maximum compression attained after initial tightening. The time required to reach 80% of maximum compression was significantly longer after subsequent compared to initial maximum compression. These findings suggest that screw retightening before surgical wound closure may slow compression loss, which could increase the likelihood of successful arthrodesis. Lag screw compression resulted in a lower percent compression loss and loss rate compared to direct compression, which was previously used to describe bone viscoelasticity.