A therapeutic Level II study by DiGiovanni et al. in the August 3, 2016 edition of The Journal of Bone & Joint Surgery examined the relationship between successful foot/ankle fusions and the amount of graft material used. The authors found that among 573 procedures in which graft material (either autograft or AUGMENT bone graft) occupied ≥50% of the cross-sectional fusion space at nine weeks, 81% were successfully fused at 24 weeks. However, among 101 procedures with <50% of the graft space filled, only 21% were successfully fused at 24 weeks.
The authors determined both graft-fill percentages at nine weeks and fusion success at 24 weeks using CT scans. The percentage of graft fill was estimated by mental summation of graft fill present in each individual CT slice of the joint, and joint fusion was determined by measuring the percentage of osseous bridging in the same semiquantitative manner.
The significant fusion rate differences between joints with and without ≥50% graft fill were consistent regardless of whether autograft or allograft was used and regardless of which joint was fused. The authors conclude that these findings “demonstrated that when a surgeon can eliminate bone-to-bone gaps in any joint intended for fusion,…such a joint has a significantly better chance of ultimately achieving fusion,” although they caution against “overpacking a joint with excessive graft material.” DiGiovanni et al. cite the need for further research “to determine the ideal amount of graft material required for a clinically relevant and impactful effect on fusion” and to help develop “graft materials that are easier to introduce and can be more precisely inserted into the intended fusion space.”
OrthoBuzz occasionally receives posts from guest bloggers. This guest post comes from Christopher E. Gross, MD, in response to the May 18, 2016 JBJS Specialty Update on Foot and Ankle Surgery.
Ankle arthritis occurs along a spectrum of severity—ranging from minor cartilage lesions to significant degenerative disease.
To preserve ankle function and to prevent possible evolution into arthritic changes, osteochondral lesions should be treated as soon as they become symptomatic. In one prospective cohort study summarized by Lin and Yeranosian in the May 18, 2016 JBJS Specialty Update, thirty patients with talar osteochondral lesions underwent arthroscopic implantation of bone marrow-derived cells onto a collagen scaffold. Patients who received adjunctive biophysical stimulation by pulsed electromagnetic fields (PEMFs) had higher AOFAS scores at one year post-operatively than those who did not.1 The proposed explanation for this outcome is that PEMFs decrease inflammatory cytokines and help differentiate stem cells into chondrocytes.
Total ankle replacements (TARs) have become a viable surgical option for patients with end-stage ankle arthritis. In a study comparing patients undergoing TAR with those undergoing arthrodesis,2 TAR patients had higher expectations of their surgery than fusion patients and were more likely to have higher satisfaction scores post-operatively. In a functional comparison of TAR and arthrodesis, Jastifer, et al. found that patients who received a TAR had an easier time walking uphill and down/upstairs.3 In another study evaluating functional biomechanics following TAR surgery, groups whose procedure included Achilles tendon lengthening were compared to those who had TAR alone.4 There were no between-group differences in functional outcomes or gait mechanics.
In a study comparing results and complications of TAR in patients with rheumatoid arthritis to patients who had ankle replacements due to either traumatic or primary arthritis, the authors found similar functional outcomes and complication rates.
Despite these many examples of TAR success in the recent literature, the procedure is not without its shortcomings. Rahm, et al.5 compared patients who underwent primary ankle fusion to those who underwent salvage ankle arthrodesis because of a failed TAR. Those who had a salvage procedure had more pain and decreased functionality compared to those who underwent a primary fusion.
Christopher E. Gross, MD is an orthopaedic surgeon specializing in foot and ankle disorders at the Medical University of South Carolina in Charleston.
- Cadossi M, Buda RE, Ramponi L, Sambri A, Natali S, Giannini S. Bone marrow-derived cells and biophysical stimulation for talar osteochondral lesions: a randomized controlled study. Foot Ankle Int. 2014 Oct;35(10):981-7.
- Younger AS, Wing KJ, Glazebrook M, Daniels TR, Dryden PJ, Lalonde KA, et al. Patient expectation and satisfaction as measures of operative outcome in end-stage ankle arthritis: a prospective cohort study of total ankle replacement versus ankle fusion. Foot Ankle Int. 2015 Feb;36(2):123-34.
- Jastifer J, Coughlin MJ, Hirose C. Performance of total ankle arthroplasty and ankle arthrodesis on uneven surfaces, stairs, and inclines: a prospective study. Foot Ankle Int. 2015 Jan;36(1):11-7.
- Queen RM, Grier AJ, Butler RJ, Nunley JA, Easley ME, Adams SB, Jr., et al. The influence of concomitant triceps surae lengthening at the time of total ankle arthroplasty on postoperative outcomes. Foot Ankle Int. 2014 Sep;35(9):863-70.
- Rahm S, Klammer G, Benninger E, Gerber F, Farshad M, Espinosa N. Inferior results of salvage arthrodesis after failed ankle replacement compared to primary arthrodesis. Foot Ankle Int. 2015 Apr;36(4):349-59.
Every month, JBJS publishes a Specialty Update—a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of all OrthoBuzz Specialty Update summaries.
This month, OrthoBuzz asked Sheldon Lin, MD and Michael Yeranosian, MD, co-authors of the May 18, 2016 Specialty Update on foot and ankle surgery, to select the five most clinically compelling findings from among the more than 50 studies they cited.
Ankle Fractures and Syndesmotic Injuries
–A randomized study compared syndesmotic fixation versus no fixation in patients with supination-external rotation (SER) IV-type ankle fractures and positive intraoperative stress tests (persistent widening of the medial clear space). At four years of follow-up researchers found no clinical or radiological differences between the two groups.1
–A randomized single-blinded trial to help determine optimal methods for soft-tissue management after ankle trauma compared standard treatment using ice and elevation with the use of multilayer compression bandages. Researchers found that multilayer compression therapy resulted in faster resolution of edema than cryotherapy.
Total Ankle Arthroplasty
–A prospective cohort study found that patients undergoing total ankle arthroplasty (TAA) had higher preoperative expectation scores than did those undergoing ankle arthrodesis. TAA patients were also more likely than arthrodesis patients to report improved postoperative satisfaction scores. Postoperative expectation and satisfaction scores in both groups were closely linked to postoperative Ankle Osteoarthritis Scale (AOS) scores. The study emphasizes the importance of preoperative patient education.2
–A randomized controlled trial looking at union rates in ankle and hindfoot arthrodesis compared the use of recombinant human platelet-derived growth factor BB homodimer (rhPDGF-BB) plus an injectable osteoconductive beta-tricalcium phosphate (β-TCP) collagen matrix to standard autograft. Complete fusion of all involved joints at 24 weeks occurred in 84% of those treated with the growth factor-matrix combination and in 65% of those treated with autograft (p <0.001).3
Patient-Reported Outcomes Assessment
–The 10-center Orthopaedic Foot & Ankle Outcomes Research (OFAR) Network conducted a three-month trial of collecting preoperative and six-month postoperative patient outcome information using the Patient Reported Outcomes Measurement Information System (PROMIS). Of the 328 patients enrolled, 76% completed the preoperative instruments and 43% completed the six-month postoperative instruments. Despite substantial loss to follow-up, the OFAR Network process enabled easy data aggregation and analysis, suggesting its utility in facilitating multicenter trials.4
- Kortekangas THJ, Pakarinen HJ, Savola O, Niinimäki J, Lepojärvi S, Ohtonen P, Flinkkilä T, Ristiniemi J. Syndesmotic fixation in supination-external rotation ankle fractures: a prospective randomized study. Foot Ankle Int. 2014 Oct;35(10):988-95. Epub 2014 Jun 24.
- Younger ASE, Wing KJ, Glazebrook M, Daniels TR, Dryden PJ, Lalonde KA, Wong H, Qian H, Penner M. Patient expectation and satisfaction as measures of operative outcome in end-stage ankle arthritis: a prospective cohort study of total ankle replacement versus ankle fusion. Foot Ankle Int. 2015 Feb;36(2):123-34.
- Daniels TR, Younger ASE, Penner MJ, Wing KJ, Le ILD, Russell IS, Lalonde KA, Evangelista PT, Quiton JD, Glazebrook M, DiGiovanni CW. Prospective randomized controlled trial of hindfoot and ankle fusions treated with rhPDGF-BB in combination with a β-TCP-collagen matrix. Foot Ankle Int. 2015 Jul;36(7):739-48.Epub 2015 Apr 6.
- Hunt KJ, Alexander I, Baumhauer J, Brodsky J, Chiodo C, Daniels T, Davis WH, Deland J, Ellis S, Hung M, Ishikawa SN, Latt LD, Phisitkul P, SooHoo NF, Yang A, Saltzman CL; OFAR (Orthopaedic Foot and Ankle Outcomes Research Network). The Orthopaedic Foot and Ankle Outcomes Research (OFAR) network: feasibility of a multicenter network for patient outcomes assessment in foot and ankle. Foot Ankle Int. 2014Sep;35(9):847-54.
In the December 16, 2015 edition of The Journal, Pellegrini et al. present the results from a cohort of 23 patients who had initially undergone ankle arthrodesis and then, due to decreasing function and increasing mid- and hindfoot pain, sought relief via conversion to an ankle arthroplasty. The good news is that this conversion provided meaningful clinical improvement in pain and function, with 87% survival of the implants over the mean 33-month follow-up.
One technical detail the authors recommend is prophylactic fixation of the malleoli as a concomitant procedure, noting that local osteopenia related to arthrodesis make malleoli prone to fracture during insertion of the tibial component. It is difficult to determine if these conversions were necessitated by poor surgical technique during the original arthrodesis, but I suspect in some cases they were. Also, considering the arthritic changes to the mid- and hindfoot joints related to arthrodesis, it is easy to understand that patients would benefit from the takedown of the fusion and return of some ankle motion to diminish the stress on those joints.
Reflecting on the findings from this clinical cohort series has prompted me to change my surgical technique for ankle arthrodesis. Formerly I hemi-sected the lateral malleolus and fixed it to the talus and distal tibia. Now I preserve the distal fibula, ensure removal of all cartilage in the medial and lateral gutters, add bone graft, and provide fixation with cancellous lag screws. This change in technique facilitates takedown of the fusion and conversion to ankle arthroplasty if necessary in the future. In my opinion, the clarion call now for ankle arthrodesis must be “save the fibula!”
Marc Swiontkowski, MD
Syndesmotic injuries of the ankle, with or without malleolar ankle fractures, are common. Studies have found that up to 40% of all athletic injuries are ankle sprains and that 5% to 10% of those involve disruption of the tibiofibular syndesmosis. However, despite the frequent occurrence of this injury and related injuries, the best treatment of syndesmotic ankle injuries remains unresolved.
In the October 2015 issue of JBJS Reviews, Jones et al. describe ankle syndesmotic injuries, noting that the normal syndesmosis widening can be up to 1.5 mm, that the syndesmosis helps to prevent excessive fibular motion during locomotion, that clinical examination to diagnose syndesmotic injury is frequently inaccurate, and that initial injury and intraoperative stress radiographs help to confirm the diagnosis. The authors note that effective treatment requires accurate reduction and stable fixation in order to allow the syndesmotic ankle ligament to heal and also to limit syndesmotic motion. This effective treatment provides the best chance for the restoration of stable ankle mechanics. Nonoperative treatment of isolated injuries is appropriate in most cases. However, the timing of weight-bearing remains controversial and the timing of and indications for fixation removal after operative treatment are also unresolved.
After an extensive review and discussion of diagnostic and treatment options, this Critical Analysis Review article provides the following recommendations for ankle syndesmotic injury. There is good evidence that ankle syndesmotic reduction and fixation provides the best results. Similarly, there is good evidence that screw fixation can be achieved with engagement of three or four cortices. There is fair evidence that screw fixation can be metallic or bioabsorbable and that screw fixation and suture button fixation have similar outcomes. There is also fair evidence that syndesmotic injuries with associated malleolar fractures have the worst outcomes. However, there is poor evidence that transsyndesmotic and suprasyndesmotic fixation have similar results. There is also poor evidence that screw removal should be performed after three months.
These recommendations are based on extensive review and analysis and should be helpful in aiding in the treatment of syndesmotic ankle injuries.
Thomas A. Einhorn, Editor
Every month, JBJS publishes a Specialty Update—a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Here is a summary of selected findings from Level I and II studies cited in the May 20, 2015 Specialty Update on foot and ankle surgery:
Talar and Calcaneal Fractures
- A prospective randomized study comparing the sinus tarsi approach with the minimally invasive approach to the calcaneus found significantly fewer wound healing complications and shorter operative times with the minimally invasive longitudinal approach, but better outcomes were noted with the sinus tarsi approach for Sanders type-IV fractures.
- An RCT comparing outcomes of operative and nonoperative treatment for displaced intra-articular calcaneal fractures found no between-group differences at one year, but a trend toward better pain scores and function was noted in the operative group at eight to twelve years.
- A prospective randomized study of treatments for severe lateral ankle sprains compared a walking boot with restricted joint mobilization for three weeks with immediate application of a functional brace. No between-group differences in pain scores or development of mechanical instability were found, but the immediate functional-brace group had better function scores and shorter recoveries.
- A randomized trial comparing neuromuscular training, bracing, and a combination of the two for managing lateral ankle sprains concluded that bracing is the dominant secondary preventive intervention.
Total Ankle Arthroplasty
- A Level II study comparing total ankle arthroplasty (TAA) with ankle arthrodesis found that both procedures improved gait postoperatively, but TAA came closer to restoring a normal gait.
- A Level II study comparing fixed and mobile-bearing TAA devices found nearly equivalent improvements in pain and function.
- A Level I study looking at TAA outcomes in relation to preoperative coronal-plane malalignment found that results were similar for ankles with a preoperative coronal-plane varus deformity of ≥10° and those with <10° of varus deformity.
Ankle and Hindfoot Arthrodesis
- A pilot RCT comparing B2A-coated ceramic granules with autograft in foot and ankle arthrodesis found that the B2A approach produced a 100% fusion rate, compared with a 92% rate in the autograft group.
- A Level II study found that weight-bearing cast immobilization provided outcomes that were similar to those of non-weight-bearing cast immobilization in non-operative management of acute Achilles tendon ruptures.
- In an RCT comparing standard-of-care orthoses with experimental pressure-based orthoses to prevent plantar foot ulcers, the experimental orthoses outperformed the standard ones.
- A Level I study investigating surgical-site infections after foot and/or ankle surgery found an increased risk of infection associated with concomitant peripheral neuropathy, even in patients without diabetes.
Ankle & Foot Pro III is one of the highest-rated apps for orthopaedic surgeons, according to TopOrthoApps, a mobile app review site. This app receives outstanding ratings in functionality, coolness, and overall features. Ankle & Foot Pro III gives a visual look at anatomy with high-level, 3-D views into muscles, tendons, nerves, vessels, ligaments and bones. The app features easily manipulated views, a “pen” feature for drawing on the screen, “pins” that identify structures of different layers, and videos demonstrating surgical procedures.
At a hospital in China, doctors took a very different approach to reattaching an amputated hand. Xiao Wei lost his right hand in an industrial accident, and his arm was severely compromised during the same accident. The dilemma that doctors faced was two-fold; saving the right hand and dealing with severe trauma to the rest of Wei’s arm. Their approach to salvaging his hand was to attach it to his ankle so the arteries and veins in the ankle would continue to supply blood to it. A month later, after his arm injuries healed and blood supply was sufficient, Xiao’s right hand was reattached to his arm. He is expected to regain full use of his hand.