Outcomes of Nonoperatively Treated Vancouver B1 Fractures: Is Failure Common?

BACKGROUND: Periprosthetic fractures (PPFx) are a severe complication of total hip and hemiarthroplasty. Surgical treatment is typically performed but can result in major morbidity. Nonoperative PPFx management may provide a successful treatment alternative in select patients. METHODS: Vancouver B1 PPFx patients treated over a 10-year period were identified. Patient demographic data were retrospectively recorded. Injury and postoperative radiographs were reviewed. There were 48 patients who met the study criteria. Patients were divided into operative and nonoperative comparative cohorts. Outcome comparisons between the 2 cohorts included 1-year mortality, unplanned surgery within 24 months of injury, fracture union rate, and return to preinjury ambulation status. RESULTS: There was no difference in 1-year mortality between the nonoperative and operative cohorts (17 versus 8%; P = .32). We found no significant difference in unplanned surgery between the nonoperative and operative groups (8.7 versus 12%; P = .71), fracture union (100 versus 96%, P = .34), or return to ambulation status (86 versus 91%; P = .86). Nonoperative fractures were minimally displaced and within the metaphyseal region of the proximal femur without stem subsidence. Nonoperative fractures with subsequent treatment failure had initial fracture extension closer to the tip of the stem compared to successfully treated nonoperative fractures (5.5 versus 10.2 centimeters; P = .02). CONCLUSION: Select nonoperatively treated patients had infrequent need for unplanned surgery, high union rate, and return to their preinjury ambulation status. Nonoperative management is not appropriate for all Vancouver B1 PPFx, but those patients who have minimally displaced meta-diaphyseal fractures and partial remaining distal fixation can be successfully treated.

Neuromuscular electrical stimulation preserves muscle strength early after total knee arthroplasty: Effects on muscle fiber size.

Loss of quadriceps strength after total knee arthroplasty (TKA) is most pronounced acutely but persists long-term, negatively impacting physical function in daily activities. Neuromuscular electrical stimulation (NMES) early after surgery is an effective adjuvant to standard of care rehabilitation (SOC) for attenuating strength loss following TKA, but the mechanisms whereby NMES maintains strength are unclear. This work aimed to determine the effects of early NMES on quadriceps strength and skeletal muscle fiber size 2 weeks after TKA compared to SOC. Patients scheduled for primary, unilateral TKA were enrolled and randomized into SOC (n = 9) or NMES plus SOC (n = 10) groups. NMES was started within 48 h of TKA, with 45-min sessions twice a day for 2 weeks. Isometric quadriceps strength was assessed preoperatively and 2 weeks following TKA. Vastus lateralis muscle biopsies of the involved leg were performed at the same time points and immunohistochemistry conducted to assess muscle fiber cross-sectional area and distinguish fiber types. Groups did not differ in age, body mass index, sex distribution, or preoperative strength. Both groups got weaker postoperatively, but the NMES group had higher normalized strength. After 2 weeks, the group receiving NMES and SOC had significantly greater MHC IIA and MHC IIA/IIX fiber size compared to SOC alone, with no group differences in MHC I fiber size. These results suggest that NMES mitigates early muscle weakness following TKA, in part, via effects on fast-twitch, type II muscle fiber size. This investigation advances our understanding of how adjuvant, early postoperative NMES aids muscle strength recovery.

Donning Gloves Before Surgical Gown Cross-contaminates the Assistant.

Background: Maintaining a sterile surgical environment is of the upmost importance in total joint arthroplasty. The surgical gown-glove interface is a frequent and known cause of bacterial contamination. A variation of the traditional staff-assisted open-gloving technique has been developed in an attempt to address this. In this method, the surgeon dons their undergloves before their gown. Although this has demonstrated improved sterility for the surgeon, no studies have considered the effects of this technique on the person assisting the surgeon. The present study was designed to investigate this. We hypothesize that the process of donning undergloves before the surgical gown leads to higher rates of contamination for the assistant. Methods: We performed a comparative study between the traditional and a gloves-first scrubbing technique. We assessed the differences in gown and glove contamination of the surgical assistant following each scrubbing event. Two surgeons applied ultraviolet light-disclosing lotion to their upper extremities and then performed each method in a randomized order with 40 surgical technologists/nurses. Blinded evaluators then quantified the amount of contamination on the surgical assistant's gown and gloves. Results: The gloves-first technique resulted in increased contamination of the surgical assistant's gloves (P = .002). There was no difference in contamination of the surgical gown (P =.982). Conclusions: Although the staff-assisted open-gloving technique may improve the sterility of the surgeon, it does so at the expense of the surgical assistant. Surgeons adopting this technique should consider donning their own undergloves or having the assistant rescrub before any further contact with the sterile environment.

Selecting a Press-fit Stem for Total Hip Arthroplasty: The Rationale and Evolution of the Modern Femoral Prosthesis.

Noncemented press-fit femoral stems predominate in total hip arthroplasty for all age groups with generally excellent long-term survivorship. The 2021 American Joint Replacement Registry reports that 96% of all elective primary total hip arthroplasties used noncemented femoral implant fixation. 1 Today, there are many styles of press-fit stems, each with supposed benefits, based on a range of design philosophies. Design aspects to consider when selecting a stem are numerous, including stem geometry, stem length, collared or collarless, material properties, and surface structure. Although most stem designs demonstrate excellent results, the differences in stem designs are intimately linked to additional factors such as ease of use/implantation, percentage of surface osseointegration, overall bone removal versus bone stock preservation, subsequent femoral stress shielding, and consideration of complexity of later revision. A surgeon with a broad understanding and appreciation of femoral stem designs should be prepared to select between the multitude of options to best serve individual patients.

Effects of total knee arthroplasty on skeletal muscle structure and function at the cellular, organellar, and molecular levels.

Total knee arthroplasty (TKA) is an important treatment option for knee osteoarthritis (OA) that improves self-reported pain and physical function, but objectively measured physical function typically remains reduced for years after surgery due, in part, to precipitous reductions in lower extremity neuromuscular function early after surgery. The present study examined intrinsic skeletal muscle adaptations during the first 5 weeks post-TKA to identify skeletal muscle attributes that may contribute to functional disability. Patients with advanced stage knee OA were evaluated prior to TKA and 5 weeks after surgery. Biopsies of the vastus lateralis were performed to assess muscle fiber size, contractility, and mitochondrial content, along with assessments of whole muscle size and function. TKA was accompanied by marked reductions in whole muscle size and strength. At the fiber (i.e., cellular) level, TKA caused profound muscle atrophy that was approximately twofold higher than that observed at the whole muscle level. TKA markedly reduced muscle fiber force production, contractile velocity, and power production, with force deficits persisting in myosin heavy chain (MHC) II fibers after expression relative to fiber size. Molecular level assessments suggest reduced strongly bound myosin-actin cross bridges and myofilament lattice stiffness as a mechanism underlying reduced force per unit fiber size. Finally, marked reductions in mitochondrial content were apparent and more prominent in the subsarcolemmal compartment. Our study represents the most comprehensive evaluation of skeletal muscle cellular adaptations to TKA and uncovers novel effects of TKA on muscle fiber size and intrinsic contractility early after surgery that may contribute to functional disability.NEW & NOTEWORTHY We report the first evaluation of the effects of total knee arthroplasty (TKA) on skeletal muscle at the cellular and subcellular levels. We found marked effects of TKA to cause skeletal muscle fiber atrophy and contractile dysfunction in older adults, as well as molecular mechanisms underlying impaired contractility. Our results reveal profound effects of TKA on muscle fiber size and intrinsic contractility early after surgery that may contribute to functional disability.

A Case of Iliopsoas Bursitis With Compressive Femoral Nerve Palsy Treated With Iliopsoas Tendon Release.

Iliopsoas bursitis is a well-established cause of groin pain after total hip arthroplasty (THA), and it can become dramatically more complex when associated with neurovascular compression. Iliopsoas bursitis may be caused by a variety of pathologies in the setting of a THA but most frequently due to a prominent acetabular component or implant wear. Here we report a rare case of a female patient presenting with iliopsoas tendonitis, an accompanying femoral nerve palsy, and debilitating pain beginning 12 years after a previously successful primary THA without apparent implant wear. Ultimately, our patient was treated successfully with iliopsoas tendon release for anterior prominence of the acetabular component.

Important Factors for Retrograde Nailing Through Total Knee Arthroplasty: A Cadaveric Study.

OBJECTIVES: Evaluate how total knee arthroplasty (TKA) implant design, femoral component size, and preoperative knee range of motion affect retrograde femoral nailing. METHODS: Cadaveric specimens were prepared for TKA with a single radius (SR) or medial pivot (MP) design and tested with cruciate retaining (CR), cruciate substituting (CS), and posterior stabilizing (PS) 9-mm liners. Knee extension identified the minimum flexion required to pass an opening reamer without impinging on TKA components. The angle between the reamer path and the femoral shaft was calculated from lateral fluoroscopic images. RESULTS: In SR TKA, the average flexion required was 70, 71, and 82 degrees for CR, CS, and PS, respectively. The required flexion in PS was significantly greater (P = 0.03). In MP TKA, the average flexion required was 74, 84, and 123 degrees for CR, CS, and PS, respectively. The required flexion was significantly greater in CS and PS designs (P < 0.0001). Femoral component size did not affect the minimum flexion required. The entry reamer resulted in 9.2 (SR) and 12.5 (MP) degrees of apex anterior deviation. CONCLUSIONS: When performing retrograde nailing through either of these TKA designs with a 12-mm opening reamer, at least 70 degrees of knee flexion is required to avoid damage to the polyethylene liner or femoral component. PS implants require significantly more flexion with both TKA designs. Femoral component size did not affect the flexion requirement. Approximately a 10-degree deviation exists between the reamer path and femoral shaft.

Reliability of a simple fluoroscopic image to assess leg length discrepancy during direct anterior approach total hip arthroplasty.

BACKGROUND: Direct anterior approach (DAA) total hip arthroplasty (THA) in a supine position provides a unique opportunity to assess leg length discrepancy (LLD) intra-operatively with fluoroscopy. Reported fluoroscopic techniques are useful but are generally complicated or costly. Despite the use of multiple techniques for leg length assessment, LLD continues to be a major post-operative source of patient dissatisfaction further emphasizing the importance of near-anatomic restoration. The utility of an alternative direct measurement of LLD on an intra-operative fluoroscopic pelvic image during DAA THA has not been reported. AIM: To determine the reliability of a novel simple intra-operative measurement of LLD using a parallel line technique on a single fluoroscopic digital image of the pelvis. METHODS: One hundred and seventy-one patients who underwent DAA THA were included for analysis. Intra-operative fluoroscopic and post-operative anterior-posterior radiographs were imported to TraumaCad and calibrated for LLD measurement. LLD was measured on each image using the right-left hip differences in lesser trochanter to pelvic reference line distances. Pelvic reference points included the teardrops and ischia. Fluoroscopic LLD was compared to the gold-standard measurement of LLD measured on a post-operative radiograph. RESULTS: Mean absolute difference in teardrop referenced LLD between fluoroscopic and post-operative radiographs was 2.17 mm and based on the ischia mean absolute difference was 2.63 mm. Linear regression of fluoroscopic and post-operative radiograph LLD based on teardrop and ischia LLD found r 2 values of 0.57 and 0.84, respectively. Mean absolute difference between fluoroscopic and post-operative x-ray LLD was within 5 mm in 95% of cases regardless of pelvic reference. CONCLUSION: This study demonstrates that a single fluoroscopic view obtained during DAA THA for leg length assessment is clinically useful.

Common Practices in Intra-Articular Corticosteroid Injection for the Treatment of Knee Osteoarthritis: A Survey of the American Association of Hip and Knee Surgeons Membership.

BACKGROUND: Knee osteoarthritis nonoperative management options remain limited. Our aim is to define the current American Association of Hip and Knee Surgeons (AAHKS) members' practices and perceptions in terms of the frequency, formulation, use of concomitant aspiration, maximum lifetime number of injections, efficacy, interval between injection and surgery and complication rates. METHODS: A 22-question survey based on Likert scale response anchors was approved and distributed by the AAHKS Research Committee to its membership by email during the Spring 2019 meeting. Data were managed with REDCap software. RESULTS: Membership response totaled 537 of 2365 (22.7%) members. Highlights include every respondent using intra-articular corticosteroid injections (ICIs) in their practice, and most use a three-month minimum interval, although the preferred interval is longer. Near consensus was found waiting three months before surgery. There was a great variability in the number of injections allowed, and injections before surgery were very common. Nearly all responders use a local anesthetic mixture with the cortisone injection, but there was great variation in corticosteroid type: methylprednisolone (42%), triamcinolone (41%), betamethasone (13.3%), and dexamethasone (3.7%). CONCLUSION: The results of our survey indicate the majority of the AAHKS members who completed the survey use ICIs routinely for treatment of knee osteoarthritis. There was near consensus in ICIs, which is effective with decreasing efficacy over serial injections, and an absolute minimum interval between injections was believed by most to be three months with no clearly defined lifetime limit and strong consensus for a three-month preoperative interval. The formulation of steroid, local anesthetic, and skin preparation technique varied greatly.

A Poster Summarizing the American Academy of Orthopaedic Surgeons Knee Osteoarthritis Clinical Practice Guideline Is a Powerful Tool for Patient Education: A Randomized Controlled Trial.

BACKGROUND: In 2013, the American Academy of Orthopaedic Surgeons (AAOS) published an evidence-based clinical practice guideline (CPG) on conservative treatment options for patients with knee osteoarthritis (OA). The purpose of this study is to evaluate the effectiveness of a poster outlining the AAOS knee OA CPG on patient comprehension and satisfaction in the clinic. METHODS: This is a prospective 2-armed randomized controlled trial. Patients were eligible if they were of age 40-85 years, had degenerative knee OA, and did not consent for surgery. Patients were randomized to nonposter (standard care) and poster rooms. Knee OA treatment options were described to the patient verbally and posters were used as a teaching tool when present. The main outcomes were comprehension and satisfaction scores on a survey. RESULTS: Of the 105 patients enrolled, 51 (48.6%) were randomized to usual care (control) and 54 (51.4%) to the intervention (poster). Poster patients outperformed control patients with an average of 55.3% ± 16.7% (mean ± SD) compared to 39.5% ± 13.3% correct answers (P < .001). And 66.7% of poster patients and 29.4% of control patients achieved an adequately informed status of >50% correct answers (P < .001; 50.5% overall). With a maximum possible score of 10, visit satisfaction scores were 9.4 ± 1.0 in poster patients and 9.2 ± 1.7 in control patients (P = .50). CONCLUSION: Patients educated using an AAOS knee CPG poster showed significant improvements in knowledge and were more likely to achieve an adequately informed status. No difference existed in visit satisfaction. A poster offers a low-cost, effective educational tool. LEVEL OF EVIDENCE: Level 1.

The Use of Cement in Hip Arthroplasty: A Contemporary Perspective.

Notable advances in hip arthroplasty implants and techniques over the past 60 years have yielded excellent survivorship of fully cemented, hybrid, and reverse hybrid total hip replacements as demonstrated in joint registries worldwide. Major advances in noncemented implants have reduced the use of cement, particularly in North America. Noncemented implants predominate today based on procedural efficiency, concern related to thromboembolic risk, and a historic belief that cement was the primary cause of osteolysis and implant loosening. With the decline of cemented techniques, press-fit fixation has become common even in osteoporotic elderly patients. Unfortunately, there is a troubling rise in intraoperative, as well as early and late postoperative periprosthetic fractures associated with the use of noncemented implants. Despite the success of noncemented fixation, an understanding of modern cement techniques and cemented implant designs is useful to mitigate the risk of periprosthetic fractures. Cemented acetabular components can be considered in elderly patients with osteoporotic or pathologic bone. Cemented stems should be considered with abnormal proximal femoral morphology, conversion of failed hip fixation, inflammatory arthritis, patient age over 75 (especially women), osteoporotic bone (Dorr C), and in the treatment of femoral neck fractures.

Comparison of Tip- Versus Hub-Oscillating Saw Blade Control in a Total Knee Arthroplasty Model.

BACKGROUND: Oscillating saws are commonly used for bone preparation in total knee arthroplasty but can cause injury to the posterior neurovascular bundle during tibial resection. Tip-oscillating saw blades are a recent innovation that could improve saw control due to decreased excursion; however, the tactile feedback to the surgeon is different. METHODS: To compare traditional hub and new tip-oscillating saw blades, 16 participants of varying levels of experience were video-recorded during composite tibial bone model resections to measure posterior saw blade plunge. Subjective perceptions of saw control and preference were also surveyed. RESULTS: Saw blade design and level of surgical experience did not produce a significant difference in posterior saw blade plunge (P > .05). Independent of saw blade design, subjects with no previous saw experience had significantly decreased posterior tibial plunge over subsequent resections. Tip-oscillating saw blades were perceived to be easier to use and control by less experienced participants (P = .0163). CONCLUSION: Tip-oscillating saw blades do not alter the risk of posterior tibial saw plunge compared with traditional saw blades.

Assessment of Early Gait Recovery After Anterior Approach Compared to Posterior Approach Total Hip Arthroplasty: A Smartphone Accelerometer-Based Study.

BACKGROUND: The influence of total hip arthroplasty surgical approach on postoperative recovery is not well understood and often debated. This study compares anterior and posterior approach (PA) gait and patient-reported Hip Osteoarthritis Outcome scores (HOOS) in the early phases of recovery. METHODS: A prospective study evaluated 20 control subjects, 35 direct anterior approach (DAA), and 34 PA total hip arthroplasty patients. Subjects were assessed preoperatively and at 1 and 4 months postoperatively with HOOS and smartphone gait assessments of gait speed, step length, cadence, step symmetry, and horizontal and vertical center of mass displacements. RESULTS: The DAA and PA groups were not different in baseline HOOS or gait characteristics except for less horizontal center of mass displacement in the DAA group. At 1 month postoperatively, the DAA group had significantly faster gait speed at self-selected (P = .02) and fastest possible gait (P = .01) and longer step length at self-selected (P = .047) and fastest gait (P = .003) compared to the PA. At 4 months, there were no differences in DAA and PA gait measures. At 1 month postoperatively there were no significant differences in HOOS, but after 4 months HOOS were significantly higher in the DAA group. CONCLUSION: There were minimal differences between the two approaches in the recovery of gait mechanics with some gait parameters particularly gait speed and step length recovery favoring the DAA at 1 month postsurgery in this nonrandomized study.

The Effect of Dexamethasone on Postoperative Blood Glucose in Patients With Type 2 Diabetes Mellitus Undergoing Total Joint Arthroplasty.

BACKGROUND: Perioperative glucocorticoids are routinely administered to patients undergoing total joint arthroplasty (TJA) to decrease postoperative pain and nausea. However, there is concern regarding the effects of glucocorticoids on perioperative glucose control in diabetes. The goal of this study is to determine if administration of preoperative dexamethasone to diabetic patients is significantly associated with hyperglycemia and increased insulin requirements in the immediate postoperative period after TJA and to identify risk factors for postoperative hyperglycemia immediately after TJA. METHODS: A retrospective review of type 2 diabetic patients undergoing TJA from 2010 to 2015 (n = 285) was undertaken to evaluate the effect of dexamethasone on postoperative glucose control. Preoperative baseline characteristics were compared between patients who did and did not receive 8 mg of intravenous dexamethasone preoperatively. Postoperative glucose and insulin requirements were evaluated with respect to dexamethasone dosing. Statistical analysis was performed using logistic regression models. RESULTS: Dexamethasone administration did not correlate with the maximum postoperative blood glucose (P = .78). There was a significantly higher initial postoperative blood glucose after intravenous dexamethasone administration (P < .01). Dexamethasone administration was associated with increased aspart insulin requirements on postoperative day 0 (P = .04). However, preoperative hemoglobin A1c was most strongly associated with postoperative glucose control. CONCLUSION: Preoperative dexamethasone administration to diabetic patients was associated with an initial increase in blood glucose and increased insulin requirement on postoperative day 0. Yet the observed effect on glucose control in diabetic patients may not outweigh the known clinical benefits of perioperative glucocorticoids.

Total Knee Bartonella henselae Infection: An Unusual Manifestation of Cat Scratch Disease: A Case Report.

CASE: This is the first clinical report of periprosthetic total joint infection caused by Bartonella henselae. A 65-year-old woman developed an acutely painful total knee 3 weeks after a cat scratch. Serial joint aspirations and tissue cultures failed to identify any organism. Diagnosis was performed with polymerase chain reaction analysis. She underwent a 2-stage revision with successful symptom resolution. CONCLUSIONS: Bartonella is an unusual cause of total knee infection requiring alternative techniques for diagnosis because cultures are unlikely to be definitive.

Competitive Running After Total Hip Arthroplasty: The World's Fastest Total Hip: A Case Report.

CASE: We report the case of a young man who underwent total hip arthroplasty (THA) for osteonecrosis at the age of 20 years, and subsequently competed in collegiate long-distance running. The pinnacle of his career was setting the school record time of 3:47.64 (min:sec) in the 1,500-m "metric mile" run (equivalent to 4:05.09 for the "English" mile). This is the fastest known time for any patient who has undergone THA. Excellent clinical and radiographic outcomes had been maintained at 6 years postoperatively. CONCLUSION: Patients who undergo arthroplasty procedures may be capable of remarkable physical accomplishments, but pursuing such feats is not advised.

Intraoperative fracture during staged total knee reimplantation in the treatment of periprosthetic infection.

Bone stock during knee reimplantation for infection is compromised and may contribute to intraoperative fracture. This study aims to describe the prevalence of said fractures. A retrospective review was performed of patients who underwent a staged TKA reimplantation for a periprosthetic infection. Patients who sustained an intraoperative fracture were analyzed. The fracture timing, location, and treatment were recorded. Fracture healing, component stability, and need for re-revision were noted. Between 1990 and 2010, 894 reimplantations were performed. Twenty-three fractures occurred in 21 patients (2.3%) with mean follow-up of 56 months (range: 4-122). Thirteen fractures occurred in femora, 7 in tibiae, and 3 in patellae. Four occurred during resection, while 19 occurred during reimplantation. Observation and wires/cables were the most common treatments utilized. At final follow-up, 91% of fractures demonstrated union and 75% of patients demonstrated stable components. Eight patients (38%) required a revision, the majority of which were performed for re-infection.

Total hip arthroplasty in the young: special emphasis on post-SCFE patients.

Slipped capital femoral epiphysis (SCFE) is a hip disorder of adolescence, which has the potential for profound implications into adulthood. SCFE patients are at risk of early joint degeneration and subsequent need for arthroplasty. The rate at which arthroplasty is required is not precisely known, but is estimated to be approximately 45% by 50 years after a slip. The femoral neck and shaft displace anteriorly and rotate externally relative to the femoral epiphysis, which remains fixed in the acetabulum. Stabilization of the physis is the goal of acute management. Despite such efforts, accelerated joint degeneration may occur over time. This progression is due to avascular necrosis, chondrolysis, or following years of femoroacetabular impingement. Total hip arthroplasty (THA) and total hip resurfacing (THR) are options for end-stage hip arthritis due to SCFE. THR is technically more challenging, with very limited ability to address deformity-related issues of impingement, decreased hip offset, and trochanteric malposition. THR, as in any metal on metal arthroplasty, may be associated with local metal sensitivity or systemic metal toxicity. Given the limited utility and potential risks, THR is currently not recommended in the majority of cases. THA, although historically demonstrating poor long-term implant performance in the young patient, has become a more reliable option recently. The potential benefits of THA are considerable, even for the young patient with end-stage hip degeneration. Certain cemented and many cementless stem designs show good long-term survival, as do current cementless cups. Advances in bearing surfaces promise to minimize wear and extend implant longevity. Ceramic on ceramic, metal on highly cross-linked polyethylene, and ceramic on highly cross-linked polyethylene bearing couples offer promise.