John Ketz

Staged posterior tibial plating for the treatment of Orthopaedic Trauma Association 43C2 and 43C3 tibial pilon fractures.

Objective: Obtaining an accurate reduction of the posterior malleolar fragment in high-energy pilon fractures can be difficult through standard anterior or medial incisions, resulting in a less than optimal articular reduction. The purpose of this study was to report on our results using a direct approach with posterior malleolar plating in combination with staged anterior fixation in high-energy pilon fractures. Design: Prospective clinical cohort. Setting: A Level I trauma and tertiary referral center. Patients/Participants: From January 1, 2005, to December 31, 2008, 19 Orthopaedic Trauma Association 43C pilon fractures (16 C3 and 3 C2) with a separate, displaced, posterior malleolar fragment were treated by the authors. Nine patients were treated with posterior plating of the tibia (PL) through a posterolateral approach followed by a staged direct anterior approach. Ten patients with similar fracture patterns were treated using standard anterior or anteromedial incisions (A) with indirect reduction of the posterior fragment. All 19 patients were available for follow-up at an average of 40 months (range, 28–54 months). Intervention: All patients were treated with open reduction and internal fixation for their pilon fractures. Main Outcome Measurements: Quality of reduction was assessed using postoperative plain radiographs and computed tomography. Serial radiographs were taken during the postoperative course to assess the progression of healing and the development of joint arthrosis. Clinical follow-up included physical examination and evaluation of the ankle using the American Orthopaedic Foot and Ankle Society Ankle & Hindfoot score, Maryland Foot Score as well as noting all complications. Results: There were no differences in injury pattern or time to surgery between groups. Of the 10 patients who were in the A group, 4 (40%) had more than 2 mm of joint incongruity at the posterior articular fracture edge as compared with no patients in the PL group as measured on postoperative computed tomography scans. At latest follow-up, 7 (70%) patients in the A group had radiographic evidence of joint space narrowing compared with 3 (33%) in the PL group. Ankle range of motion for the A group was 35.8° versus 34.2° for the PL group (nonsignificant). There were 2 delayed wound healing complications in the A group with one deep infection in the PL group. Two patients in the A group required arthrodesis procedures resulting from posttraumatic arthrosis compared with none in the PL group. No significant difference was seen in postoperative complications across both groups. The average Maryland Foot Score and American Orthopaedic Foot and Ankle Society/Ankle & Hindfoot score for the PL group was 86.4/85.2 compared with 69.4/76.4 for the A group. Conclusions: The addition of a posterior lateral approach offers direct visualization for reduction of the posterior distal fragment of the tibial pilon. Although the joint surface itself cannot be visualized, this reduction allows the anterior components to be secured to a stable posterior fragment at a later date. This technique improved our ability to subsequently obtain an anatomic articular reduction based on computed tomography scans and preservation of the tibiotalar joint space at a minimum 1-year follow-up. Furthermore, it correlated with an improvement in clinical outcomes with increases in Maryland Foot Score and Ankle & Hindfoot score for the posterior plating group. Although promising, continued follow-up will be needed to determine the long-term outcome using this technique for treating tibial pilon fractures.

Dynamic Kinematic and Plantar Pressure Changes Following Cheilectomy for Hallux Rigidus: A Mid-Term Followup

Background: Hallux rigidus leads to significant loss of first metatarsophalangeal (MTP) joint motion. Cheilectomy surgery aims to increase motion, decrease pain, and facilitate a return to activity. Limited data exist regarding restoration of dynamic kinematics and loading responses following cheilectomy. This prospective study assessed three-dimensional in vivo first MTP joint kinematics and loading characteristics following cheilectomy. Materials and Methods: Twenty patients were evaluated prior to undergoing cheilectomy for hallux rigidus. Fifteen subjects returned for mid-term followup at 1.7 years. Eleven subjects were surveyed at 6 years. Plantar pressure data were acquired during barefoot walking. Comparisons of average pressures were determined for 4 different regions of the foot. Pressure differences were compared within, and between symptomatic and asymptomatic feet. First MTP joint dorsiflexion and abduction were assessed during standing, active motion and gait. Results: Only four out of 15 patients showed increased lateral metatarsal loading preoperatively. Pressures shifted medially following surgery. Significant increases in dorsiflexion were found for active motion (pre-op = 13.3 ± 12.7 degrees; post-op = 21.7 ± 14.7 degrees, p = 0.005) and dorsiflexion during gait (pre-op = 19.3 ± 12 degrees; post-op = 30.8 ± 14.8 degrees, p = 0.01). Hallux abduction also increased. During standing, the hallux remained in plantarflexion relative to the first metatarsal. Conclusion: Cheilectomy was effective in maintaining balanced plantar loading. First MTP motion increased but dorsiflexion was still less than normative values. The magnitude of dorsiflexion relative to abduction favorably improved during gait. These findings suggest that kinematics continue to be altered and may lead to further degenerative joint changes. Exploration of alternative surgical techniques is warranted.

Preoperative PROMIS Scores Predict Postoperative Success in Foot and Ankle Patients.

Background: The use of patient-reported outcomes continues to expand beyond the scope of clinical research to involve standard of care assessments across orthopedic practices. It is currently unclear how to interpret and apply this information in the daily care of patients in a foot and ankle clinic. We prospectively examined the relationship between preoperative patient-reported outcomes (PROMIS Physical Function, Pain Interference and Depression scores), determined minimal clinical important differences for these values, and assessed if these preoperative values were predictors of improvement after operative intervention. Methods: Prospective collection of all consecutive patient visits to a multisurgeon tertiary foot and ankle clinic was obtained between February 2015 and April 2016. This consisted of 16 023 unique visits across 7996 patients, with 3611 new patients. Patients undergoing elective operative intervention were identified by ICD-9 and CPT code. PROMIS physical function, pain interference, and depression scores were assessed at initial and follow-up visits. Minimum clinically important differences (MCIDs) were calculated using a distribution-based method. Receiver operating characteristic (ROC) curves were calculated to determine whether preoperative PROMIS scores were predictive of achieving MCID. Cutoff values for PROMIS scores that would predict achieving MCID and not achieving MCID with 95% specificity were determined. Prognostic pre- and posttest probabilities based off these cutoffs were calculated. Patients with a minimum of 7-month follow-up (mean 9.9) who completed all PROMIS domains were included, resulting in 61 patients. Results: ROC curves demonstrated that preoperative physical function scores were predictive of postoperative improvement in physical function (area under the curve [AUC] 0.83). Similarly, preoperative pain interference scores were predictive of postoperative pain improvement (AUC 0.73) and preoperative depression scores were also predictive of postoperative depression improvement (AUC 0.74). Patients with preoperative physical function T score below 29.7 had an 83% probability of achieving a clinically meaningful improvement in function as defined by MCID. Patients with preoperative physical function T score above 42 had a 94% probability of failing to achieve MCID. Patients with preoperative pain above 67.2 had a 66% probability of achieving MCID, whereas patients with preoperative pain below 55 had a 95% probability of failing to achieve MCID. Patients with preoperative depression below 41.5 had a 90% probability of failing to achieve MCID. Conclusion: Patient-reported outcomes (PROMIS) scores obtained preoperatively predicted improvement in foot and ankle surgery. Threshold levels in physical function, pain interference, and depression can be shared with patients as they decide whether surgery is a good option and helps place a numerical value on patient expectations. Physical function scores below 29.7 were likely to improve with surgery, whereas those patients with scores above 42 were unlikely to make gains in function. Patients with pain scores less than 55 were similarly unlikely to improve, whereas those with scores above 67 had clinically significant pain reduction postoperatively. Reported prognostic cutoff values help to provide guidance to both the surgeon and the patient and can aid in shared decision making for treatment. Level of Evidence: Level II, prognostic study.

The Salvage of Complex Hindfoot Problems with Use of a Custom Talar Total Ankle Prosthesis

BACKGROUND There has been recent interest in the use of a custom long-stemmed talar component for salvage of failed total ankle replacement or for management of combined ankle and hindfoot pathology. The purpose of this study was to retrospectively review prospective data on patients who underwent total ankle arthroplasty with a custom long-stemmed talar prosthesis. METHODS From November 2004 to February 2006, thirty-three custom total ankle arthroplasties were performed in thirty-two patients. The indication for this prosthesis was stage-IV adult-acquired flatfoot deformity in six patients (19%), failure of a prior total ankle replacement because of severe subsidence and loosening of the talar component in thirteen (41%), and combined arthritis of the ankle and hindfoot joints in thirteen patients (41%; fourteen ankles). Patients were assessed for range of motion, radiographic results, and functional outcomes with use of the Short Form-36 (SF-36) subscale scores, American Orthopaedic Foot & Ankle (AOFAS) hindfoot score, and the Maryland Foot Score (MFS) at a minimum of four years. RESULTS All patients were followed for an average of 58.6 months (minimum, fifty-two months) There was an overall increase in the total arc of motion following surgery from an average (and standard deviation) of 21.3° ± 14° preoperatively to 32.2° ± 11° postoperatively (p < 0.05). Subsidence (<3 mm) was noted in three patients. One patient had asymptomatic osteolysis around the talar stem. The mean Physical Component Summary score on the SF-36 was 28.2 ± 5.6 preoperatively and increased to 39.7 ± 6.5 postoperatively (p < 0.05). The mean SF-36 Mental Component Summary value increased from 42.2 ± 13.8 preoperatively to 50.8 ± 12.6 postoperatively (p < 0.05). The mean MFS was 47 ± 13 preoperatively and increased to 75 ± 10 postoperatively (p < 0.05). The average AOFAS hindfoot score increased from 41 ± 16 preoperatively to 68 ± 12 postoperatively (p < 0.05). There were three failures at greater than thirty-six months after surgery. CONCLUSIONS Our data indicate that the use of a custom long-stemmed talar component, either placed primarily in patients with ankle and hindfoot arthritis or used as a revision prosthesis in patients with a failed total ankle replacement, is promising.

Establishment of an index with increased sensitivity for assessing murine arthritis

The goals of our study were to establish quantitative outcomes for assessing murine knee arthritis and develop an Arthritis Index that incorporates multiple outcomes into a single calculation that provides enhanced sensitivity. Using an accepted model of meniscal/ligamentous injury (MLI)‐induced osteoarthritis (OA), we assessed mouse knee arthritis using several approaches. Histology‐based methods were performed to visualize joint tissues including articular cartilage and subchondral bone. Accepted histologic scoring methods and histomorphometry were performed to grade cartilage degeneration and determine articular cartilage area, respectively. MicroCT was used to visualize and quantify the bony structures of the joint including osteophytes and joint bone volume. A statistical algorithm was then developed that combined histologic scores and cartilage areas into a single Arthritis Index. MLI induced progressive, OA‐like articular cartilage degeneration characterized by increasing (worsening) histologic score and decreasing cartilage area. MicroCT revealed osteophytes and increased joint bone volume between the femoral and tibial physes following MLI. Lastly, an Arthritis Index calculation was established, which incorporated histologic scoring and cartilage area. The Arthritis Index provided enhanced quantitative sensitivity in assessing the level of joint degeneration compared to either histologic scoring or cartilage area determination alone; when using the Index, between 29% and 43% fewer samples are needed to establish statistical significance in studies of murine arthritis. Arthritis in the mouse knee can be quantitatively assessed by histologic scoring, measuring cartilage area, and determining joint bone volume. Enhanced sensitivity can be achieved by performing the Arthritis Index calculation, a novel method for quantitatively assessing mouse knee arthritis.

Ultrasound strain mapping of Achilles tendon compressive strain patterns during dorsiflexion

Heel lifts are commonly prescribed to patients with Achilles tendinopathy, yet little is known about the effect on tendon compressive strain. The purposes of the current study were to (1) develop a valid and reliable ultrasound elastography technique and algorithm to measure compressive strain of human Achilles tendon in vivo, (2) examine the effects of ankle dorsiflexion (lowering via controlled removal of a heel lift and partial squat) on compressive strain of the Achilles tendon insertion and (3) examine the relative compressive strain between the deep and superficial regions of the Achilles tendon insertion. All tasks started in a position equivalent to standing with a 30mm heel lift. An ultrasound transducer positioned over the Achilles tendon insertion was used to capture radiofrequency images. A non-rigid image registration-based algorithm was used to estimate compressive strain of the tendon, which was divided into 2 regions (superficial, deep). The bland-Altman test and intraclass correlation coefficient were used to test validity and reliability. One-way repeated measures ANOVA was used to compare compressive strain between regions and across tasks. Compressive strain was accurately and reliably (ICC>0.75) quantified. There was greater compressive strain during the combined task of lowering and partial squat compared to the lowering (P=.001) and partial squat (P<.001) tasks separately. There was greater compressive strain in the deep region of the tendon compared to the superficial for all tasks (P=.001). While these findings need to be examined in a pathological population, heel lifts may reduce tendon compressive strain during daily activities.

Suppressive Effects of Insulin on Tumor Necrosis Factor-Dependent Early Osteoarthritic Changes Associated with Obesity and Type 2 Diabetes Mellitus

Obesity is a state of chronic inflammation that is associated with insulin resistance and type 2 diabetes mellitus (DM), as well as an increased risk of osteoarthritis (OA). This study was undertaken to define the links between obesity‐associated inflammation, insulin resistance, and OA, by testing the hypotheses that 1) tumor necrosis factor (TNF) is critical in mediating these pathologic changes in OA, and 2) insulin has direct effects on the synovial joint that are compromised by insulin resistance.

Mechanical changes in the Achilles tendon due to insertional Achilles tendinopathy.

Insertional Achilles tendinopathy (IAT) is a painful and debilitating condition that responds poorly to non-surgical interventions. It is thought that this disease may originate from compression of the Achilles tendon due to calcaneal impingement. Thus, compressive mechanical changes associated with IAT may elucidate its etiology and offer clues to guide effective treatment. However, the mechanical properties of IAT tissue have not been characterized. Therefore, the objective of this study was to measure the mechanical properties of excised IAT tissue and compare with healthy cadaveric control tissue. Tissue from the Achilles tendon insertion was acquired from healthy donors and from patients undergoing debridement surgery for IAT. Several tissue specimens from each donor were then mechanically tested under cyclic unconfined compression and the acquired data was analyzed to determine the distribution of mechanical properties for each donor. While the median mechanical properties of tissue excised from IAT tendons were not significantly different than healthy tissue, the distribution of mechanical properties within each donor was dramatically altered. In particular, healthy tendons contained more low modulus (compliant) and high transition strain specimens than IAT tendons, as evidenced by a significantly lower 25th percentile secant modulus and higher 75th percentile transition strain. Furthermore, these parameters were significantly correlated with symptom severity. Finally, it was found that preconditioning and slow loading both reduced the secant modulus of healthy and IAT specimens, suggesting that slow, controlled ankle dorsiflexion prior to activity may help IAT patients manage disease-associated pain.

Peroneal Tendon Instability in Intra-Articular Calcaneus Fractures: A Retrospective Comparative Study and a New Surgical Technique.

Objective: To compare the prevalence of peroneal tendon instability as determined by intraoperative evaluation versus preoperative computed tomography (CT) scans, and to identify specific risk factors that correlate with tendon instability. Design: Retrospective comparative study. Setting: Level 1 trauma hospital. Patients: Patients with operatively treated intra-articular calcaneus fractures managed between January 1, 2002 and December 31, 2012 were reviewed for evidence of peroneal tendon instability. Of 254 fractures, 155 intra-articular calcaneus fractures met inclusion criteria and were available for final analysis. Intervention: Operative notes were reviewed to confirm intraoperative testing for superior peroneal retinaculum (SPR) integrity and peroneal tendon stability. Preoperative CT scan and plain radiographs were evaluated for presence of peroneal tendon dislocation, fibular fracture or “fleck” sign, excessive lateral wall displacement, and/or calcaneal fracture-dislocation. Main Outcome Measures: Peroneal tendon stability was determined with intraoperative assessment of the intact SPR and its confluence with the peroneal tendon sheath. The incidence of peroneal tendon instability on intraoperative assessment was compared with preoperatively identified tendon dislocation on CT scan. Prevalence of peroneal tendon dislocation was determined using each diagnostic method. Risk factors for tendon instability were identified using a multivariate regression model. Results: There was significantly higher prevalence of peroneal tendon instability as determined by preoperative imaging (30%; n = 47/155) compared with intraoperative retinaculum testing (11.6%; n = 18/155) (P < 0.001). Intraoperative tendon instability was significantly associated with increased fracture classification severity, fibular fracture/“fleck” sign, and fracture-dislocation. Conclusions: Intraoperative evaluation of the SPR should be used in conjunction with preoperative imaging for diagnosis of peroneal instability in the setting of operatively treated, intra-articular calcaneus fractures. Level of Evidence: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Quality and Utility of Immediate Formal Postoperative Radiographs in Ankle Fractures

Background: Patients who undergo internal fixation of ankle fractures commonly have postoperative imaging performed immediately after surgery. As these patients typically are typically immobilized, radiographs provide limited visualization. The purpose of this study was to evaluate the utility and quality of formal radiographs performed immediately following ankle fracture surgery. Methods: Ankle fractures undergoing open reduction and internal fixation at a single institution from January 1, 2011, to January 1, 2013, were reviewed. Intraoperative and formal postoperative radiographs were evaluated using defined parameters. The postoperative images were compared with the intraoperative fluoroscopic images in terms of quality. Postoperative complications were evaluated in terms of fracture displacement, hardware malpositioning, and need for return to the operating room. A total of 411 patients with 413 ankle fractures underwent surgical fixation, with 271 patients undergoing formal postoperative radiographs. Results: Twenty-eight patients (10.3%) had 3 good quality postoperative views of the ankle, with the lateral (35.2%) and mortise (41.3%) views least commonly performed with good technique. None of the patients without radiographs had a complication that could have been detected earlier using postoperative radiographs. No patients required return to the operating room based on immediate postoperative radiographs. Postoperative radiographs cost