Who Benefits from Manipulation under Anesthesia Following Total Knee Arthroplasty?

Arthrofibrosis is a multifactorial process that results in decreased knee range of motion (ROM). Manipulation under anesthesia (MUA) is commonly regarded as the preferred initial treatment of arthrofibrosis following total knee arthroplasty (TKA). There have been no well-controlled studies demonstrating that MUA effectively increases ROM in patients who develop arthrofibrosis after TKA when compared with routine care. The purpose of this study was to determine whether MUA had any advantage over routine care in the treatment of patients who developed arthrofibrosis following TKA. The authors identified patients who underwent primary TKA at the authors' institution between 2010 and 2014 and had flexion ≤ 100 degrees at early follow-up. Knees were grouped based on how the arthrofibrosis was treated: those who underwent MUA and those who received routine care. Knee flexion was captured preoperatively (prior to TKA), at early follow-up (prior to MUA or routine care), and at 1-year follow up. Flexion change from early follow-up to 1 year was calculated. The average flexion at 1-year follow-up was not significantly different between the two groups (106.1 ± 11.7 degrees in the routine care group versus 106.3 ± 12.8 degrees in the MUA group). The MUA group had a greater proportion of patients with flexion gains > 20 degrees at final follow-up when compared with patients who underwent routine care (56% vs. 8%, p < 0.0001). This study demonstrates that patients with decreased ROM at early follow-up after primary TKA can expect greater ROM increase at 1-year follow-up if they undergo MUA compared with patients who undergo routine care. (Journal of Surgical Orthopaedic Advances 33(1):033-036, 2024).

Early results of fixed-bearing unicompartmental knee replacement designed for the lateral compartment.

BACKGROUND: Isolated lateral compartment knee arthritis is less prevalent than medial. While the reported results of medial unicompartmental knee replacement (UKR) have been good and comparable to total knee replacement, the results of lateral UKR have been mixed. We present the short-term results and survivorship of a fixed-bearing UKR designed specifically for the lateral compartment. METHODS: We report the result of 130 primary fixed-bearing lateral Oxford (FLO) UKRs (123 patients) performed between 2015 and 2019 with a minimum follow-up of 1 year. The indications for lateral UKR were: isolated lateral osteoarthritis (n = 122), post-trauma (n = 5) and osteonecrosis (n = 3). The mean age was 69.1 (± 11.6), mean BMI 28.4 (± 4.9), 66.9% female, 60% right-sided, and mean follow-up 3 (range 1-4.8 years, standard deviation ± 1) years. The primary outcome measure was the Oxford knee score (OKS). Survival analysis was performed with "revision for any reason", "reoperation", and "implant failure" as the endpoints. RESULTS: Six patients died from unrelated reasons. None of the implants failed. One required the addition of a medial UKR for medial arthritis. There were no other reoperations. At 4 years, the survival for implant failure was 100% and for both revision and all reoperations was 99.5% (95% CI 96.7-99.9%). At the last review, at a mean of 3 years, the mean Oxford knee score was 41. CONCLUSION: The good survivorship and outcome scores suggest that UKR designed for the lateral compartment is an excellent alternative to total knee replacement in selected patients with isolated lateral tibiofemoral arthritis at short-term follow-up.

A guide to debridement, antibiotics, and implant retention.

Debridement, antibiotics, and implant retention (DAIR) is an alternative management strategy for the treatment of periprosthetic joint infection (PJI). While infection eradication rates are lower with DAIR, the benefits including decreased morbidity, improved functional outcomes, and decreased cost may justify the risks when considering this form of treatment compared to traditional one or two stage exchange arthroplasty. Implant longevity in the setting of a successful DAIR is similar to matched patients who have not experienced a PJI. An experienced arthroplasty surgeon well versed in extensile exposure should perform the DAIR. This procedure should not be viewed as a simple "washout." While PJI may be considered a surgical urgency, DAIR can be performed on a planned list if it allows for appropriate staffing and implants for the procedure. Arthroscopic irrigation may be performed for a patient in extremis but it should not be viewed as a definitive procedure to address PJI. Keys to a successful DAIR include accurate tissue sampling to determine the infective organism, meticulous, radical debridement, and exchange of modular components if possible. A multidisciplinary team (MDT) including an infectious disease specialist should be involved prior to surgery in order to guide appropriate antimicrobial therapy throughout the patient's course of treatment. In the article below we present our indications, considerations, and technique for performing a DAIR for PJI for hip and knee arthroplasty.

Debridement, antibiotics and implant retention (DAIR) for the management of knee prosthetic joint infection.

BACKGROUND: While two-stage revision arthroplasty is viewed as the gold standard for the treatment of knee periprosthetic joint infection (PJI) in terms of infection eradication, it is associated with significant cost along with patient morbidity and mortality. Debridement, antibiotics, and implant retention (DAIR) is an attractive option as it has demonstrated better patient outcomes, comparable implant longevity to primary arthroplasty, and significantly reduced cost when successful. Given the heterogeneity of what is defined as a DAIR the literature is highly variable in terms of its efficacy from the perspective of infection eradication. METHODS: In the setting of a previously well-functioning, well-fixed arthroplasty with an acceptable soft tissue envelope and a treatable organism we report our methods for proceeding with a DAIR procedure, both unicompartmental and total knee. RESULTS: With the above methods we have demonstrated improved patient outcomes when compared to one- or two-stage arthroplasty with lower patient morbidity. Implant longevity in the setting of a successful DAIR is equivalent to those of a primary arthroplasty. CONCLUSIONS: With appropriate indications and good surgical technique as described we believe DAIR is an excellent option in the treatment of periprosthetic joint infection. We hope that with a well-defined protocol as outlined we can gain a better understanding of the efficacy of DAIR procedure with more homogeneity to the procedure to better define when they are most successful while improving patient outcomes and reducing cost.

Aspirin used for venous thromboembolism prophylaxis in total hip arthroplasty decreases heterotopic ossification.

BACKGROUND: Heterotopic ossification (HO) is a known complication of total hip arthroplasty (THA) that can lead to persistent pain, stiffness, nerve impingement, and instability. Aspirin (ASA) has become an increasingly popular method of venous thromboembolism (VTE) prophylaxis, given its availability, ease of use, and relative safety. Although indomethacin has been commonly used for HO prophylaxis, we wanted to determine whether ASA, given the similar mechanism of action, may be effective in reducing the risk of HO in routine unilateral, primary THA when already being used for VTE prophylaxis. METHODS: The postoperative radiographs of 222 consecutive patients undergoing unilateral, primary THA with cementless fixation were evaluated for HO formation using the Brooker classification immediately before and after surgeon protocol shifted to routine utilization of ASA as VTE prophylaxis in low-risk patients. RESULTS: HO was detected in 13 of 99 (13.1%) THAs prescribed ASA for VTE prophylaxis (11 grade I, 1 grade II, 1 grade III) compared with 38 of 123 (30.9%) THAs prescribed non-ASA chemoprophylaxis (26 grade I, 7 grade II, 4 grade III, 1 grade IV). Significantly more THAs in the non-ASA cohort developed HO (P < .01). There was no significant difference in the distribution of HO severity between cohorts (P = .61). CONCLUSIONS: ASA may be effective as monotherapy for both VTE and HO reduction in low-risk patients undergoing unilateral primary arthroplasty with cementless fixation.

Standardized Opioid Prescription Protocol Reduces Opioid Consumption After Total Joint Arthroplasty.

Previous studies demonstrate routine overprescription of pain medications after total joint arthroplasty (TJA). A standardized reduced opioid prescription protocol for TJA was initiated at our institution, which we hypothesized would lead to a reduction in opioid consumption compared with patients who had surgery before initiation of the new protocol. METHODS: We evaluated 97 consecutive opioid-naive patients undergoing primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) using a standardized opioid prescription protocol (standardized group). A control subject group consisted of 99 patients undergoing TKA and THA just before the adaptation of the standardized prescribing protocol (historic group). Postoperatively, patients brought their remaining pain medication to their 1-month follow-up visit. The number of pills consumed was counted and converted into oral morphine equivalents (OME). Current pain level and the need for pain medication refill was assessed. RESULTS: Among TKA patients, mean opioid consumption in the standardized group (48.5 pills; 432 OME) was markedly less than the historic group (76.2 pills; 903 OME) (both P < 0.01). Refills were required in 50% of the standardized group and 29% of the historic group (P = 0.038). Average pain scores for the standardized and historic groups were 2.3 and 3.2, respectively (P = 0.057). Among THA patients, mean opioid consumption in the standardized group (19.1 pills; 200 OME) was markedly less than the historic group (41.3 pills; 504 OME) (both P < 0.01). Refills were required in 16% of the standardized group and 8% of the historic group (P = 0.263). Average pain scores for the standardized and historic groups were 1.7 and 1.8, respectively (P = 0.608). DISCUSSION: Initiation of a standardized opioid prescribing protocol after TJA for opioid-naive patients led to a reduction in opioid consumption, but resulted in an increased need for refills.

Regional Ulnar Nerve Strain Following Decompression and Anterior Subcutaneous Transposition in Patients With Cubital Tunnel Syndrome.

PURPOSE: Simple decompression and anterior subcutaneous transposition are effective surgical interventions for cubital tunnel syndrome and yield similarly favorable outcomes. However, a substantial proportion of patients demonstrate unsatisfactory outcomes for reasons that remain unclear. We compared effects of decompression and transposition on regional ulnar nerve strain to better understand the biomechanical impacts of each strategy. METHODS: Patients diagnosed with cubital tunnel syndrome and scheduled for anterior subcutaneous transposition surgery were enrolled. Simple decompression, circumferential decompression, and anterior transposition of the ulnar nerve were performed during the course of the transposition procedure. Regional ulnar nerve strain around the elbow was measured for each surgical intervention based on 4 wrist and elbow joint configurations. RESULTS: With elbow extension at 180°, both circumferential decompression and anterior transposition resulted in approximately 68% higher nerve strains than simple decompression. Conversely, with elbow flexion, simple decompression resulted in higher average strains than anterior transposition. Limited regional differences in strain were observed for any surgical intervention with elbow extension. However, with elbow flexion, strains were higher in distal and central regions compared with the proximal region within all surgical groups, and proximal region strain was higher after simple decompression compared with anterior transposition. CONCLUSIONS: As predicted by the altered anatomic course, anterior transposition results in lower ulnar nerve strains than simple decompression during elbow flexion and higher nerve strains during elbow extension. Irrespective of anatomic course, circumferential release of paraneurial tissues may also influence nerve strain. Nerve strain varies regionally and is influenced by surgery and joint configuration. CLINICAL RELEVANCE: Our data provide insight into how surgery resolves and redistributes traction on the ulnar nerve. These findings may help inform which surgical procedure to perform for a specific patient, guide rehabilitation protocols, and suggest regions of anatomic concern during index and revision surgery.

Altered ulnar nerve kinematic behavior in a cadaver model of entrapment.

BACKGROUND: Ulnar nerve entrapment at the elbow is more than a compressive lesion of the nerve. The tensile biomechanical consequences of entrapment are currently marginally understood. OBJECTIVE: To evaluate the effects of tethering on the kinematics of the ulnar nerve as a model of entrapment neuropathy. METHODS: The ulnar nerve was exposed in 7 fresh cadaver arms, and markers were placed at 1-cm increments along the nerve, centered on the retrocondylar region. Baseline translation (pure sliding) and strain (stretch) were measured in response to progressively increasing tension produced by varying configurations of elbow flexion and wrist extension. Then the nerves were tethered by suturing to the cubital tunnel retinaculum and again exposed to progressively increasing tension from joint positioning. RESULTS: In the native condition, for all joint configurations, the articular segment of the ulnar nerve exhibited greater strain than segments proximal and distal to the elbow, with a maximum strain of 28 ± 1% and translation of 11.6 ± 1.8 mm distally. Tethering the ulnar nerve suppressed translation, and the distal segment experienced strains that were more than 50% greater than its maximum strain in an untethered state. CONCLUSION: This work provides a framework for evaluating regional nerve kinematics. Suppressed translation due to tethering shifted the location of high strain from articular to more distal regions of the ulnar nerve. The authors hypothesize that deformation is thus shifted to a region of the nerve less accustomed to high strains, thereby contributing to the development of ulnar neuropathy.

Peripheral nerve lengthening as a regenerative strategy.

Peripheral nerve injury impairs motor, sensory, and autonomic function, incurring substantial financial costs and diminished quality of life. For large nerve gaps, proximal lesions, or chronic nerve injury, the prognosis for recovery is particularly poor, even with autografts, the current gold standard for treating small to moderate nerve gaps. In vivo elongation of intact proximal stumps towards the injured distal stumps of severed peripheral nerves may offer a promising new strategy to treat nerve injury. This review describes several nerve lengthening strategies, including a novel internal fixator device that enables rapid and distal reconnection of proximal and distal nerve stumps.

A prospective, randomized, double-blinded single-site control study comparing blood loss prevention of tranexamic acid (TXA) to epsilon aminocaproic acid (EACA) for corrective spinal surgery.

BACKGROUND: Multilevel spinal fusion surgery has typically been associated with significant blood loss. To limit both the need for transfusions and co-morbidities associated with blood loss, the use of anti-fibrinolytic agents has been proposed. While there is some literature comparing the effectiveness of tranexamic acid (TXA) to epsilon aminocaproic acid (EACA) in cardiac procedures, there is currently no literature directly comparing TXA to EACA in orthopedic surgery. METHODS/DESIGN: Here we propose a prospective, randomized, double-blinded control study evaluating the effects of TXA, EACA, and placebo for treatment of adolescent idiopathic scoliosis (AIS), neuromuscular scoliosis (NMS), and adult deformity (AD) via corrective spinal surgery. Efficacy will be determined by intraoperative and postoperative blood loss. Other clinical outcomes that will be compared include transfusion rates, preoperative and postoperative hemodynamic values, and length of hospital stay after the procedure. DISCUSSION: The primary goal of the study is to determine perioperative blood loss as a measure of the efficacy of TXA, EACA, and placebo. Based on current literature and the mechanism by which the medications act, we hypothesize that TXA will be more effective at reducing blood loss than EACA or placebo and result in improved patient outcomes. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT00958581.

Bone grafting options for lumbar spine surgery: a review examining clinical efficacy and complications.

BACKGROUND: Iliac crest harvest has been considered the "gold standard" at producing successful arthrodesis of the lumbar spine but is also associated with many donor-site morbidities. Many alternatives have been used to avoid iliac crest harvest, including autologous bone from other donor sites, allogeneic bone, ceramics, and recombinant human bone morphogenetic proteins (rhBMPs). This review will highlight the properties and preparations of these graft types and their potential complications and reported clinical efficacy. METHODS: A Medline search was conducted via PubMed by use of the following terms in various combinations: lumbar fusion, freeze-dried allograft, fresh-frozen allograft, autograft, iliac crest, demineralized bone matrix, rhBMP-2, rhBMP-7, scoliosis, bone marrow aspirate, HEALOS, coralline hydroxyapatite, beta tricalcium phosphate, synthetic, ceramics, spinal fusion, PLF, PLIF, ALIF, and TLIF. Only articles written in English were assessed for appropriate material. Related articles were also assessed depending on the content of articles found in the original literature search. CONCLUSIONS: Although iliac crest remains the gold standard, reported success with alternative approaches, especially in combination, has shown promise. Stronger evidence with limited sources of potential bias is necessary to provide a clear picture of their clinical efficacy.