Severe inwardly pointing knee after medial patellofemoral ligament reconstruction: a case report.

We report the case of a 26-year-old woman who presented with a profound gait disturbance and total disability following a medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar dislocation. It is common knowledge that patellar instability is associated with multiple risk factors, including but not limited to loss of the MPFL, trochlear dysplasia, patella alta, an abnormally placed tibial tuberosity on the tibia, quadriceps contracture, genu valgum, excess of femoral anteversion, excess of external tibial torsion, and foot pronation. Since the relative importance of each is unknown, it is imperative that pre-operative evaluation considers these. Two additional surgeries failed to improve her severe disability. Subsequent evaluation, 8 years after her initial MPFL reconstruction, revealed the presence of an excess of external tibial torsion and genu valgum. Complete resolution of disability resulted following tibial osteotomy, suggesting the importance of torsional deformity contributing to patellofemoral instability. Gait disturbance is an unrecognised complication after MPFL reconstruction.

Torsional Abnormality: The Forgotten Issue in the Diagnosis and Treatment of the Anterior Knee Pain Patient.

Currently, no one doubts that the vast majority of anterior knee pain (AKP) cases do not need surgery [...].

The incidence of complications after derotational femoral and/or tibial osteotomies in patellofemoral disorders in adolescents and active young patients: a systematic review with meta-analysis.

PURPOSE: To quantify the risk of perioperative and postoperative complications of derotational femoral and/or tibial osteotomies in patellofemoral disorders (anterior knee pain and patellar instability) in adolescents and active young patients. METHODS: MEDLINE, EMBASE, Cochrane and Scopus databases were used to identify studies published from database inception and June 30, 2021. Meta-analysis was performed to pool the rates of complications related to femur and tibia osteotomies. Values of proportion of complications were expressed as proportions and 95% confidence intervals (CI) and then transformed using a Freeman Tukey double arcsine transformation. Meta-regression was used to explore factors that potentially may influence on heterogeneity such as year of publication, quality of the included studies and site of the osteotomy. RESULTS: The 22 studies identified included a total of 648 derotational osteotomies in 494 patients. Studies consisted of 20 case series (non-comparative) and 2 comparative observational non-randomized cohorts. Tibial osteotomies showed higher risk of complications than femoral osteotomies (random pooled prevalence 9%; 95% CI 4-15% versus 1%; 95% CI 0-5%, respectively, p < 0.01). The meta-regression analysis of the articles showed that the only parameters responsible of the variance in number of complications were the osteotomy site. CONCLUSIONS: Derotational femoral and/or tibial osteotomy is a safe surgical procedure in the treatment of patellofemoral disorders (anterior knee pain and patellar instability) in adolescents and active young people. LEVEL OF EVIDENCE: IV.

Elimination of the Femoral Neck in Measuring Femoral Version Allows for Less Variance in Interobserver Reliability.

Background and Objectives: Producing consistent measures of femoral version amongst observers are necessary to allow for an assessment of version for possible corrective procedures. The purpose of this study was to compare two computed tomography (CT)-based techniques for the reliability of measuring femoral version amongst observers. Materials and Methods: Review was performed for 15 patients post-femoral nailing for comminuted (Winquist III and IV) femoral shaft fractures where CT scanograms were obtained. Two CT-based techniques were utilized to measure femoral version by five observers. Results: The mean femoral version, when utilizing a proximal line drawn down the center of the femoral head-neck through CT, was 9.50 ± 4.82°, while the method utilizing the head and shaft at lesser trochanter centers produced a mean version of 18.73 ± 2.69°. A significant difference was noted between these two (p ≤ 0.001). The method of measuring in the center of the femoral head and neck produced an intraclass correlation coefficient (ICC) of 0.960 with a 95% confidence interval lower bound of 0.909 and upper bound of 0.982. For the method assessing version via the center of the head and shaft at the lesser trochanter region, the ICC was 0.993 with a 95% confidence interval lower bound of 0.987 and an upper bound of 0.996. Conclusions: The method of measuring version proximally through a CT image of the femoral head-neck versus overlaying the femoral head with the femoral shaft at the most prominent aspect of the lesser trochanter produces differing version measurements by roughly 10° while yielding an almost perfect interobserver reliability in the new technique. Both techniques result in significantly high interobserver reliability.

A Validated, Automated, 3-Dimensional Method to Reliably Measure Tibial Torsion.

BACKGROUND: Tibial torsion is a twist in the tibia measured as an angle between a proximal axis line and a distal axis line. Abnormal torsion has been associated with a variety of painful clinical syndromes of the lower limb. Measurements of normal tibial torsion reported by different authors vary by 100% (ranging from 20° to 42°), making it impossible to determine normal and pathological levels. PURPOSE: To address the problem of unreliable measurements, this study was conducted to define an automated, validated computer method to calculate tibial torsion. Reliability was compared with current clinical methods. The difference between measurements of torsion generated from computed tomography (CT) and magnetic resonance imaging (MRI) scans of the same bone, and between males and females, was assessed. STUDY DESIGN: Controlled laboratory study. METHODS: Previous methods of analyzing tibial torsion were reviewed, and limitations were identified. An automated measurement method to address these limitations was defined. A total of 56 cadaveric and patient tibiae (mean ± SD age, 37 ± 15 years; range, 17-71 years; 28 female) underwent CT scanning, and 3 blinded assessors made torsion measurements by applying 2 current clinical methods and the automated method defined in the present article. Intraclass correlation coefficient (ICC) values were calculated. Further, 12 cadaveric tibiae were scanned by MRI, stripped of tissue, and measured using a structured light (SL) scanner. Differences between torsion values obtained from CT, SL, and MRI scans, and between males and females, were compared using t tests. SPSS was used for all statistical analysis. RESULTS: When the automated method was used, the tibiae had a mean external torsion of 29°± 11° (range, 9°-65). Automated torsion assessment had excellent reliability (ICC, 1), whereas current methods had good reliability (ICC, 0.78-0.81). No significant difference was found between the torsion values calculated from SL and CT (P = .802), SL and MRI (P = .708), or MRI and CT scans (P = .826). CONCLUSION: The use of software to automatically perform measurements ensures consistency, time efficiency, validity, and accuracy not possible with manual measurements, which are dependent on assessor experience. CLINICAL RELEVANCE: We recommend that this method be adopted in clinical practice to establish databases of normal and pathological tibial torsion reference values and ultimately guide management of related conditions.

Successful two-stage revision of Lactobacillus infection of a total knee arthroplasty and literature review.

BACKGROUND: Lactobacillus has been identified as the causative organism in only two total joint arthroplasties: one total hip arthroplasty (THA) and one total knee arthroplasty (TKA). The THA was a litigious case that was treated successfully with a one-stage revision, and the patient with the TKA ultimately required above-knee amputation. We present the first case report of a Lactobacillus infection of a TKA that was treated successfully with a two-stage revision TKA. METHODS: Case report and literature review. CASE REPORT: While undergoing a revision left TKA for persistent pain, a 55-year-old Caucasian female was found to have a Lactobacillus infection by intra-operative culture. After an extended course of intravenous (IV) antibiotics, the patient underwent a successful two-stage revision of her prosthesis. CONCLUSION: Lactobacillus has been appearing more frequently in the literature as a pathogen in patients with compromised immune systems. Orthopedic implant infection with Lactobacillus has only been reported twice, with poorly defined treatment regimens and inconsistent results in both cases. The present report provides orthopedic surgeons and infectious diseases specialists with a treatment algorithm consisting of a two-stage revision of a TKA and a second-line IV antibiotic regimen that may be able to eradicate a Lactobacillus infection of an orthopedic prosthesis with retention of the extremity containing the implant and re-implantation of a functioning prosthesis.

Implant and limb alignment outcomes for conventional and navigated unicompartmental knee arthroplasty.

Accurate implant positioning and restoration of lower limb alignment are major requirements for successful long-term results in unicompartmental knee arthroplasty (UKA). Alignment accuracy was compared between navigated-UKA (nUKA) and conventional-UKA (cUKA) groups using a retrospective matched case-control study (n=129, 58 nUKA, 71 cUKA). Mechanical axis (MA), hip-knee-ankle angle (HKA°), coronal implant alignment, and tibial implant posterior slope were measured. No statistically significant difference was observed when comparing MA, HKA° or coronal implant alignment (p>0.05). Statistical significance was seen with tibial component posterior slope (p=0.04, nUKA 4.2°, cUKA 2.9°); and between intra-operative navigationally determined HKA° and post-operative whole-leg standing (WLS) film HKA°. Navigation does not significantly improve UKA alignment compared to conventional methods. Further studies are needed to justify the use of this technology in UKA.

The female knee: anatomic variations and the female-specific total knee design.

UNLABELLED: The concept and need for a gender-specific or female-specific total knee prosthesis have generated interest and discussion in the orthopaedic community and the general public. This concept relies on the assumption of a need for such a design and the opinion that there are major anatomic differences between male and female knees. Most of the information regarding this subject has been disseminated through print and Internet advertisements, and through direct-to-patient television and magazine promotions. These sources and a recent article in a peer-reviewed journal, which support the need for a female-specific implant design, have proposed three gender-based anatomic differences: (1) an increased Q angle, (2) less prominence of the anterior medial and anterior lateral femoral condyles, and (3) reduced medial-lateral to anterior-posterior femoral condylar aspect ratio. We examined the peer-reviewed literature to determine whether women have had worse results than men after traditional TKAs. We found women have equal or better results than men. In addition, we reviewed the evidence presented to support these three anatomic differences. We conclude the first two proposed differences do not exist, and the third is so small that it likely has no clinical effect. LEVEL OF EVIDENCE: Level IV, systematic review. See the Guidelines for Authors for a complete description of levels of evidence.

Patellofemoral syndrome a paradigm for current surgical strategies.

The literature regarding suggested treatments for patellofemoral problems is often conflicting and confusing. In this discussion I present the approach I take in evaluating and considering surgery for patients with any of a wide variety of anterior knee pain problems. It has been useful to concentrate on the biomechanics--the mechanical consequence to each tissue affected by any surgical change. In the proposed paradigm, it is assumed that pain is the result of an abnormal load--related either to tension or compression--being applied to each tissue in question. The challenge is to understand how and why that abnormal load was generated. It is essential to make an independent assessment of the condition of the lower limb skeleton, the patellofemoral ligaments, and the trochlear and patellar articular cartilage in each patient. While only a long book can address this subject in detail, this discussion provides a guide for formulating an analysis of the key issues when planning the operative treatment of patellofemoral pain and dysfunction.

Medial patellofemoral ligament reconstruction in patients with lateral patellar instability and trochlear dysplasia.

BACKGROUND: Reconstruction of the medial patellofemoral ligament has been proven to restore stability in patients with lateral patellar instability. No study to date has examined the results in a patient population with the predisposing factor of femoral trochlear dysplasia. HYPOTHESIS: Reconstruction of the medial patellofemoral ligament restores stability and provides pain relief in patients who have lateral patellar instability in association with trochlear dysplasia. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Thirty-four patients with chronic patellar instability and trochlear dysplasia were treated with medial patellofemoral ligament reconstruction using an adductor tendon autograft, bone-quadriceps tendon autograft, or bone-patellar tendon allograft. All patients were evaluated preoperatively and postoperatively with Kujala, Lysholm, and Tegner scores at a minimum of 24 months. RESULTS: Thirty-four patients were followed for a mean of 66.5 months (range, 24-130 months) after surgery. Kujala scores improved from 53.3 to 90.7, Lysholm scores improved from 52.4 to 92.1, and Tegner activity scores improved from 3.1 to 5.1. All improvements were highly statistically significant (P < .001). No statistical difference was found between the postoperative Lysholm, Kujala, and Tegner scores and the degree of dysplasia, graft type, or degree of symptoms. There were 85.3% and 91.1% good and excellent results based on Kujala and Lysholm scores, respectively. No recurrent dislocations have occurred. CONCLUSION: Medial patellofemoral ligament reconstruction provides excellent long-term pain relief and functional return in patients with patellar instability and femoral trochlear dysplasia. In addition, reconstruction prevents recurrent dislocation, despite the diminished bony constraint of a dysplastic trochlea.

Fresh osteochondral allografts for patellofemoral arthritis: long-term followup.

UNLABELLED: Treatment of patellofemoral osteoarthritis in young patients is a challenge for orthopaedic surgeons. Concern about loosening and wear in active young people render arthroplasty more suitable for older patients. Osteochondral allografts may be a good alternative, but reports of experience with such grafts in patellofemoral joints are limited. We retrospectively reviewed our results with fresh osteochondral allografts. Our hypothesis was that these grafts provide relief from osteoarthritis, improve knee function, and delay prosthetic knee replacement. From 1986 to 1999, 14 fresh patellofemoral or patellar allografts were implanted in knees of 11 patients younger than 55 years and diagnosed with advanced secondary osteoarthritis. At last followup (average, 10 years; range, 2.5-17.5 years), eight grafts were in place, four for more than 10 years and two for more than 5 years. Of the nonsurviving allografts, three survived more than 10 years. Radiographs of the knees with intact allografts showed mild or no degenerative changes. Average Knee Society scores improved (preoperative to last followup), with knee scores improving from 46 points (range, 38-60 points) to 82 points (range, 35-100 points) and functional scores from 30 points (range, 10-60 points) to 75 points (range, 20-100 points). Fresh osteochondral allografts can provide relief from the arthritic condition, improve knee function, and delay prosthetic knee replacement. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Stabilization of the clavicle after distal resection: a biomechanical study.

BACKGROUND: The potential destabilizing effect of distal clavicle resection has received limited attention. HYPOTHESIS: Suturing the coracoacromial ligament to the undersurface of the distal clavicle after resection could counter clavicle instability. STUDY DESIGN: Controlled laboratory study. METHODS: The effect of ligament augmentation on posterior translation of the clavicle after resection was evaluated using 12 fresh-frozen cadaveric shoulders. Posterior clavicular displacement was measured after the application of a 70-N load under 4 different conditions: (1) the intact joint, (2) after distal clavicle resection, (3) clavicle resection plus acromioclavicular capsular ligament repair, and (4) clavicle resection plus acromioclavicular capsular ligament repair plus coracoacromial ligament augmentation. RESULTS: Mean displacements for each of the test conditions were as follows: (1) 5.60 mm, (2) 7.38 mm, (3) 7.54 mm, and (4) 6.34 mm. A 32% increase in posterior translation was measured after resection compared to the intact specimen. No reduction in posterior displacement was noted after capsular repair; however, displacement decreased significantly when capsular repair was coupled with ligament augmentation. CONCLUSIONS: Results suggest that the destabilizing effect of clavicle resection can be partially countered by the proposed ligament augmentation. CLINICAL RELEVANCE: That the destabilizing effect of clavicle resection can be partially countered by the proposed ligament augmentation may be particularly relevant in cases of resection for posttraumatic arthritis after acromioclavicular separation in which some degree of preexisting acromioclavicular capsular attenuation and consequently acromioclavicular joint laxity may be presumed.

Lateral patellofemoral ligament reconstruction.

Abstract Medial dislocation of the patella is a disabling condition; there are several reports in the literature describing this condition and its association with failed lateral retinacular release. The diagnosis and treatment of medial subluxation of the patella may be difficult. Direct repair or imbrication of the lateral retinaculum provides initial stability but a noticeable increase in medial excursion usually reappears. In this article, we describe a simple and reproducible technique to reconstruct the lateral patellofemoral ligament with autogenous tissue that is based on the basic principles of all ligament reconstruction. Reconstruction of the lateral patellofemoral ligament is useful in eliminating the symptoms related to medial instability of the patella after failed lateral retinacular release; however, it must be considered a salvage procedure because it does not address the pathomechanics that led to the initial patellofemoral symptoms.

Immune response in patients receiving fresh osteochondral allografts.

Immunologic response to cartilage-specific protein (CSP) antigens was tested in patients treated with fresh osteochondral allografts. Eight of 14 allograft recipients showed immune reactivity against CSP, whereas only 2 of 14 controls were reactive (P<.05). The molecular weights of the most common immunoreactive proteins were 220 kd and 95 kd. The precise identity of these proteins could not be determined using standard anticollagen antibodies. These data indicate the presence of antibodies to CSP--which supports the concept of immunologic response to the cartilage component of osteochondral allografts.

Patellofemoral malalignment: looking beyond the viewbox.

A clear understanding of the pathophysiology of anterior knee pain is inhibited by the use of imprecise, poorly defined, and often interchanged words, such as malalignment, patellar alignment, maltracking, subluxation, dislocation, and congruence. The literature is filled with articles regarding the diagnosis, "malalignment of the patella," most of which give no precise diagnosis. This article presents a definition of malalignment and a plea for rational descriptive and scientific analysis. Much of what is described is based on theory, not facts. These ideas are supported by clinical experience and logical analysis, but very little in the way of scientific data. Most of the data involve radiographic images, which present only one piece of the puzzle.

Biologic resurfacing of the patella: current status.

The techniques of biologic resurfacing of the patella, like other joint surfaces, are still evolving. Currently none of them is free from criticism. In this regard it is our hope that progress in the basic science will offer in the near future new and more optimistic therapeutic possibilities (i.e., the restoration of a reparative cartilage that is structurally and functionally comparable to the native one). The greater expectancies come perhaps from the present experimental investigations about the combined use of tissue-engineered implants embedded with staminal cells and growth factors. Many problems remain to be solved, however, before reliable applicability in humans. From a general point of view, stem cells obtained from various sources (e.g., adult bone marrow, umbilical cord) offer the same finalities as the embryonic stem cells, without the ethical obstacles related to the latter. Therefore, it may be that restoration of part or all of the articular surface of a joint will be possible by way of these mesenchymal progenitors that have the ability to differentiate into the chondrogenic and osteogenic lines, which is required for the restoration of the various layers of a normal articular cartilage and subchondral bone.