Lateral Compartment Research Articles

Ultrasound-guided, minimally invasive looped thread fasciotomy for chronic exertional compartment syndrome of the lower leg: A cadaveric feasibility study

Background– Chronic exertional compartment syndrome (CECS) is an exertional pain syndrome that typically affects the lower legs of participants involved in high-intensity running or marching activities. Surgical open fasciotomy is the standard treatment for recalcitrant cases of CECS. Alternative, minimally invasive fasciotomy techniques are emerging which may reduce rates of procedural complications and expedite recovery. The standard fasciotomy procedure for CECS may be improved by looped thread release with additional image guidance. The aim of this study was to describe and evaluate a novel technique of ultrasound-guided, minimally invasive looped thread fasciotomy for release of anterior and lateral compartments of the leg in a cadaveric model. We hypothesized that a fasciotomy of this type would be effective in achieving a target fasciotomy length of 80% of the length of a muscle compartment while avoiding injury to neurovascular structures. Materials and methods– We conducted a controlled laboratory study. Two proceduralists performed anterior and lateral compartment fasciotomies on ten lightly embalmed cadaveric legs. A total of twenty compartment releases were completed, using an ultrasound-guided, percutaneous looped cutting thread technique. The specimens were evaluated for length and completeness of fasciotomy, as well as any inadvertent injury to muscle, tendon, or neurovascular structures. Completeness of fasciotomy was compared between the anterior and lateral compartments. Results– Eighteen of twenty (90%) fasciotomies were continuous. Fasciotomy length was consistently under target (72% complete). Completeness of lateral compartment release was significantly more likely to be under target compared to anterior compartment release (65% vs. 79%, p ​= ​0.014). Sixteen of twenty (80%) fasciotomies incurred no iatrogenic soft tissue injury; no injuries to nerves or vessels were observed. Discussion –Ultrasound-guided, minimally invasive looped thread fasciotomy of the anterior and lateral leg compartments is feasible and can be successfully performed in a cadaveric model with low risk to neurovascular structures. However, further investigation is needed to improve completeness of release prior to recommendation for clinical use.

Outcomes of Distal Femoral Osteotomy for Valgus Malalignment: A Systematic Review and Meta-analysis of Closing Wedge Versus Opening Wedge Techniques

Background: Valgus knee deformity increases the risk for lateral articular chondral damage, contributing to earlier onset and accelerated progression of osteoarthritis. Distal femoral osteotomy (DFO) unloads the lateral joint compartment and can be performed using closing wedge (CW) or opening wedge (OW) techniques. Purpose: To perform a systematic review and meta-analysis for patients with valgus knee deformity undergoing DFO to determine differences in patient-reported outcome measures (PROMs), complications, and survival rates, comparing CW versus OW DFO. Study Design: Systematic review, Level of evidence, 4. Methods: A literature review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines utilizing PubMed, Cochrane Database, Ovid/MEDLINE, and Scopus. Inclusion criteria consisted of studies reporting outcomes in patients undergoing CW or OW DFO for the treatment of valgus knee deformities with symptomatic lateral compartment pathology with a minimum 2-year follow-up. PROMs and complications were analyzed using random-effects modeling to identify differences in outcomes as a function of surgical technique. Long-term survival data, defined as conversion to total knee arthroplasty, were analyzed using a multiple metaregression model as a function of individual study follow-up time points and surgical technique. Results: In total, we included 23 retrospective studies (n = 619 knees), of which 10 studies (n = 271 knees) reported outcomes after CW DFO and 13 studies (n = 348 knees) reported on OW DFO outcomes. Good to excellent clinical outcomes were reported in PROMs when compared with preoperative values with both techniques, while no significant differences between techniques were appreciated on functional Knee Society Scores and Tegner scores. No significant differences were appreciated in the incidence of complications reported in patients undergoing CW (20%) versus OW (33%) DFO (P = .432). Pain requiring hardware removal was the most commonly reported complication in both groups. The survival rate for CW DFO was 81.5% (mean follow-up, 8.8 ± 4.3 years) compared with 90.5% for OW DFO (mean follow-up, 4.5 ± 1.5 years). Multiple metaregression demonstrated that patient follow-up (P < .001) was significantly associated with knee survival, while surgical technique (P = .810) was not a predictor of clinical failure. Conclusions: Both CW and OW DFO techniques were associated with good to excellent clinical outcomes with no significant differences in PROMs based on technique. Pain requiring hardware removal was the most common complication in both techniques, while long-term survivability was found to be a function of follow-up and not surgical technique. Technique selection should be based on shared patient-physician decision making with an emphasis on surgeon preference and technique familiarity.

Reliability and Validity of an MRI-Based Knee Sagittal Alignment Measure in a Pediatric Cohort.

Magnetic resonance imaging (MRI) sagittal alignment is a measure that has been described and validated in the adult population as a means of distinguishing normal knees from those with anterior cruciate ligament (ACL) injury, but this measure has not been formally assessed among pediatric patients. The purpose of this study was to (1) assess the reliability of this MRI-based measure in a pediatric cohort, and (2) validate its ability to distinguish between ACL and non-ACL-injured knees in this population. A consecutive series of knee MRI examinations performed at our center were reviewed to identify studies of pediatric patients (1) with ACL injury, and (2) without significant pathology. Patient age, sex, physeal status (open, closing, or closed), knee laterality, and magnet strength (1.5 or 3-Tesla) were collected. The sagittal alignment was measured in both medial and lateral tibiofemoral compartments using a previously described method. Mean anterior tibial translation was then calculated for each study. Inter-rater and intrarater reliability testing was performed on a subset of randomly-selected patients from each cohort by three raters by calculating intraclass correlation coefficients. Sagittal alignment measurements of all patients were then completed by a single author after reliability was confirmed. The medial and lateral compartment translation and mean anterior tibial translation measurements of normal and ACL-injured knees were compared. Inclusion criteria were met by 131 studies: 86 from uninjured knees (normal cohort) and 45 knees with ACL injury (ACL cohort). Studies were performed at a mean age of 13.4 with a near equivalent sex distribution. Inter-rater and intrarater reliability were good to excellent for all measures for patients in both normal and ACL cohorts. Normal and ACL-injured knees demonstrated a significant difference in anterior tibial translation in all measured regions. The mean anterior tibia translation for ACL-injured knees was 2.01 mm (95% confidence interval: 1.03-2.98) versus -0.44 mm (95% confidence interval: -0.89-0.014). This study identified good to excellent inter-rater and intrarater reliability of knee sagittal alignment measurements among pediatric patients. It also demonstrated a significant difference in medial compartment, lateral compartment, and mean tibial translation in patients with and without ACL injury, validating previous findings demonstrated in adult cohorts. These findings may be useful in assisting providers in the confirmation of suspected ACL injury and insufficiency and guide operative management in cases of clinical uncertainty. Level III-retrospective comparative study.

Normal range of motion at the hip show different pressure behavior in the lateral and acetabular compartments: a cadaveric investigation

PurposeThe techniques used previously to assess intracapsular pressures did not allow the assessment of pressure variations in both compartments throughout the entire range of motion without puncturing the capsular tissue. Our hypothesis was that the intra-capsular pressure would be different in the lateral and acetabular compartment depending on the movement assessed.MethodsEight hip joints from four cadaveric specimens (78.5 ± 7.9 years) were assessed using intra-osseous tunnels reaching the lateral and acetabular compartments. Using injector adaptors, 2.7 ml of liquid were inserted in both compartments to simulate synovial liquid. Optic pressure transducers were used to measure pressure variations. We manually performed hip adduction, abduction, extension, flexion and internal rotation at 90° of flexion.ResultsHip extension and internal rotation show the highest intra-capsular pressures in the lateral compartment with increases of 20.56 ± 19.29 and 19.27 ± 18.96 mmHg, respectively. Hip abduction and hip internal rotation showed depressurisations of − 16.86 ± 18.01 and − 31.88 ± 30.71 mmHg in the acetabular compartment, respectively. The pressures measured in the lateral compartment and in the acetabular compartment were significantly (P < 0.05) different for the hip abduction, 90° of flexion and internal rotation. Pressure variations showed that maximum intracapsular fluid pressures in the lateral compartment occur at maximum range of motion for all movements.ConclusionAs an increase in pressure may produce hip pain, clinician should assess pain at maximum range of motion in the lateral compartment. The pressure measured in the acetabular compartment vary depending on the hip position. The movements assessed are used in clinical practice to evaluate hip integrity and might bring pain. The pressure variations throughout the entire range of motion are a relevant information during hip clinical assessment and might help clinicians to better understand the manifestations of pain.

Synchronous lateral lymph node metastases from papillary and follicular thyroid carcinoma: case report and review of the literature

BackgroundFollicular thyroid carcinomas (FTCs) rarely metastasize to regional lymph nodes, and descriptions of synchronous lateral lymph node metastases of FTC and papillary thyroid carcinoma (PTC) are lacking.Case PresentationWe describe a 43-year-old female with a preoperative cytology indicating a right-sided PTC with lateral lymph node metastases. She underwent a total thyroidectomy and central and lateral lymph node dissection, and histopathology confirmed a multifocal tall cell variant PTC together with a 12 mm minimally invasive FTC in the ipsilateral lobe. While the central compartment demonstrated metastatic PTC, the lateral compartment contained PTC metastases alongside a 15 mm large follicular-patterned mass in a separate lymph node. As the cells lacked PTC associated nuclear changes, the possibility of a lateral lymph node metastasis of FTC was considered, with the possibility of ectopic thyroid tissue as a differential diagnosis. By utilizing next-generation sequencing, a Q61R NRAS mutation was pinpointed, thus proving the tissue as tumorous. The patient underwent radioiodine treatment and is currently monitored following a negative whole-body scan.ConclusionsThis is probably the first case report of a patient with co-existing lateral lymph node PTC and FTC metastases. Consulting previous publications, there is currently a gap of knowledge in terms of how patients with regional FTC metastases should be followed-up and treated, especially when co-occurring with spread high-risk PTC subtypes. Moreover, what guides a seemingly indolent FTC to spread via the lymphatic system remains to be defined from a molecular standpoint.

The Lawrence D. Dorr Surgical Techniques & Technologies Award: Patient Acceptable Symptom State (PASS) in Medial and Lateral Unicompartmental Knee Arthroplasty: Does the Status of the ACL Impact Outcomes?

BackgroundThe aim of this study is to determine if there is a difference in the percentage of patients who reach Patient Acceptable Symptom State (PASS) when comparing anterior cruciate ligament (ACL)-deficient and ACL-intact knees following fixed-bearing medial and lateral unicompartmental knee arthroplasty (UKA). MethodsA consecutive series of 215 knees that underwent UKA (medial = 158, lateral = 57) were included in the study. The Knee Osteoarthritis Outcome Score functional score [KOOS activities of daily living (ADL)] and KOOS Sport were used as the primary outcome variables. A KOOS ADL PASS of 87.5 and KOOS Sport PASS of 43.8 were previously described for total knee arthroplasty (TKA). Failure was defined as conversion to TKA. ResultsThere were 157 in the ACL-intact group and 58 in the ACL-deficient group. Conversion to TKA was 3.7%. The failure rate in the ACL-deficient group was 5% (3/58) and 3% (5/157) in the ACL-intact group (P = .447). The mean survival for the entire group was 18.1 years (95% confidence interval 17.6-18.6). At 10 years, the survival was 94.3% (standard error = 0.028) in the ACL-deficient group and 97.6% (standard error = 0.014) in the ACL-intact group. At a mean 10 ± 3.5 years, with 93% follow-up, 83% in the ACL-deficient group and 80% in the ACL-intact group reached PASS for KOOS ADL (P = .218). For KOOS Sport, 85% of the ACL-deficient group compared to 81% in the ACL-intact group (P = .374) reached PASS. ConclusionThe ACL-deficient cohort results were not significantly different compared to ACL-intact knees in both medial and lateral compartment UKA. Fixed-bearing medial and lateral UKA resulted in low failure rate and excellent long-term outcomes.

Comparison between Ultrasonography and CT in Diagnosis of Cervical Lymph Node Metastasis of Papillary Thyroid Carcinoma

Objective To evaluate the efficacy of ultrasound and computed tomography (CT) in diagnosing cervical lymph node metastasis (CLNM) of papillary thyroid carcinoma (PTC). Methods The patients with PTC treated by surgery in the Chinese PLA General Hospital from January 2016 to January 2021 were selected for analysis.All the patients underwent preoperative ultrasound and CT examinations,the diagnostic values of which for CLNM were retrospectively analyzed. Results A total of 322 PTC patients were enrolled in this study,including 242 with CLNM and 80 with non-CLNM.The CLNM group and non-CLNM group had significant differences in age,tumor size,and maximum size of lateral CLNM (χ2=20.34,27.34,and 4.30,respectively,all P<0.001).For the central compartment,lateral compartment,and overall compartment,ultrasound diagnosis showed higher sensitivity (χ 2=82.26,P<0.001;χ2=114.01,P<0.001;χ2=82.26,P<0.001) and accuracy (χ2=20.27,P<0.001;χ2=15.56,P<0.001;χ2=44.00,P<0.001) than CT,and had no significant differences from ultrasound combined with CT (all P>0.05).However,ultrasound diagnosis had lower specificity than CT (χ2=17.01,P<0.001;χ2=21.29,P<0.001) in the central compartment and lateral compartment.Receiver operating characteristic curve analysis showed that in the central compartment,lateral compartment,and overall compartment,ultrasound diagnosis had larger AUC than CT (Z=2.99,P=0.003;Z=3.86,P<0.001;Z=4.47,P<0.001) and had no significant difference from ultrasound combined with CT (Z=1.87,P=0.062;Z=1.68,P=0.093;Z=1.61,P=0.107). Conclusions Ultrasound and CT have their own advantages in the diagnosis of central and lateral CLNM.In general,ultrasound has better performance than CT in the diagnosis of CLNM.

Prior Anterior Cruciate Ligament Reconstruction Does Not Compromise the Functional Outcomes of Medial Unicompartmental Knee Arthroplasty Although Revision for Progressive Arthritis May Occur Earlier.

Anterior cruciate ligament (ACL) deficiency is commonly considered a contraindication for unicompartmental knee arthroplasty (UKA). The purpose of this study is to compare the outcomes of UKA after prior ACL reconstruction (rACL cohort) to UKA with an intact native ACL (nACL cohort). Forty-five patients from 3 institutions who underwent medial UKA after prior rACL were matched by age, gender, preoperative function scores, and body mass index to 90 patients who underwent UKA with an intact nACL. Primary outcomes were Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, Oxford Knee Scores, Knee Society Functional Scores, and Kellgren-Lawrence scores in the unresurfaced, lateral tibiofemoral compartment. Secondary outcomes were postoperative complications and the need for revision to TKA. At a mean of 3.6 years, all PROMs improved significantly with no differences identified between groups. The incidence of revision TKA was similar between cohorts (P= 1.00); however, the mean time to revision for progressive osteoarthritis was 4.0 years in the nACL group and 2.2 years in the rACL group. Twenty percent of rACL patients had a postoperative complication compared to 8% in the nACL group. Despite presenting with a similar degree of lateral arthritis, a greater percentage of patients developed Kellgren-Lawrence scores of ≥3 in the rACL cohort (9%) than in the nACL cohort (0%). A previously reconstructed ACL does not appear to compromise the short-term functional outcomes of UKA; however, there is a higher rate of minor complications and progression of lateral compartment arthritis, which should be considered with patients in the shared decision process.

A Balanced Arthroscopic Debridement of the Inner Layer of the Knee Retinaculum Increases the Tibiofemoral Joint Space Width.

Introduction Traditional techniques can enlarge the medial tibiofemoral joint space width (JSW) for meniscal repairs, but a remnant ligament laxity may be developed. Alternatively, the debridement of the inner retinaculum layer may result in a balanced JSW without causing extra-ligament damage (retinaculum layers II and collateral ligament). Purpose The purpose of this study was to determine whether a concentric arthroscopic debridement of the inner retinaculum layer increases the tibiofemoral JSW in patients with meniscal injuries. Secondarily, we determine whether the increase in JSW is symmetrical between compartments and describe the rate of complications and patient satisfaction. Method Twenty middle-aged (15 male and five female) patients diagnosed with acute meniscal injury aged 36 ± 12 years were enrolled. The patients were submitted to an arthroscopic debridement of the inner layer of the knee retinaculum for both the medial and lateral compartments. The tibiofemoral JSW was measured intra-articularly using a custom instrument. A two-way ANOVA for repeated measures was used to compare the JSW. A Bland–Altman analysis and test-retest analysis were performed. Results The JSW increased following the debridement of the inner retinaculum layer, for both the medial and lateral compartments (p < 0.001). No complications were identified, and the patients were satisfied with the intervention. The minimal detectable change and bias of the custom instrument were 0.06 mm and 0.02 mm, respectively. Conclusion The debridement allows a clinically important (>1 mm) symmetric tibiofemoral JSW enlargement. The technique suggests favoring the diagnosis of meniscus injuries and manipulating arthroscopic instruments without secondary complications after one year.

The role of surgery in the palliation of advanced pelvic malignancy

Advanced pelvic malignancy, regardless of the cancer of origin, is often multivisceral and complex. The management of advanced pelvic malignancy is resource-intensive and requires multidisciplinary input. The definition of resectability is evolving with improving multimodal therapy, preoperative staging and optimisation, perioperative care, and advanced surgical techniques. Pelvic exenteration is a highly morbid procedure and has been shown to improve survival and quality of life when performed with a curative intent. Unresectable distant solid organ or lymph node metastases and an inability to achieve a clear resection margin preclude curative pelvic exenteration.Patients with advanced pelvic malignancy who are deemed palliative are mostly managed by non-operative treatment such as chemo-, radio-, immuno-, hormonal therapy, pain management and palliative care, as well as allied health and psychosocial support team. These patients may present with severe and debilitating symptoms including intractable pain, ulcerating/proliferating tumour, pelvic fistula/sepsis/bleeding, urinary and bowel obstruction/incontinence. Interventional radiological and surgical procedures such as percutaneous drainage, nephrostomy, intestinal and urinary diversion, intestinal bypass, and venting gastrostomy have an important role in symptom control and improving quality of life.Palliative pelvic exenteration should be carefully considered along with life expectancy, patient wishes and tumour characteristics. Comprehensive discussion with patient is crucial to achieve realistic expectations. These patients should not only be discussed in a multidisciplinary team meeting with palliative care input, but also be referred for a formal palliative care consultation. Tumour anatomical extent should be considered both for and against pelvic exenteration whether involving the posterior compartment i.e. sacrectomy; lateral compartment incorporating neurovascular bundle and the anterior compartment requiring pubic bone excision as all can be associated with high morbidity rates. Patient recovery may be protracted too if surgery is complicated by perineal wound or flap breakdown in cases necessitating wide perineal skin and soft tissue excision. Furthermore, evidence from quality of life and cost-effectiveness studies do not provide robust data to support pelvic exenteration with palliative intent. Whilst a relatively ‘straightforward’ central soft tissue pelvic exenteration may offer reasonable symptomatic relief in a patient with an acceptable life expectancy, palliative pelvic exenteration overall should only be considered in highly selected patients.

Are Patellofemoral Ligaments and Retinacula Distinct Structures of the Knee Joint? An Anatomic, Histological and Magnetic Resonance Imaging Study.

There is disagreement regarding the description of the patellofemoral ligaments (PFLs), considered by some authors as capsular thickening and by others as independent ligaments. It was hypothesised that the PFLs and retinacula are structures with different histological features. The aim of this study was to describe the stabilising structures of the patella in detail and to determine if the PFLs and retinacula are different and separable structures from a macroscopic, microscopic and imaging viewpoint. An anatomical study was performed on eight knees from five cadavers (mean age, 56.2 years; range, 35–63 years), and a histological study was conducted on specimens from nine patients having a mean age of 65 years (range 35–84 years) who had undergone surgical knee procedures. The imaging study was based on 100 MRIs (96 patients). The mean age was 46 years (range 16–88), and the study analysed the capsular-ligamentous structures. In the medial compartment, the layers and structures were as follows: superficial layer, medial retinaculum; intermediate layer, Medial Collateral Ligament (MCL), Posterior Oblique Ligament (POL) and Medial Patellofemoral Ligament (MPFL); deep layer, deep part of the MCL and joint capsule. In the lateral compartment, the layers and structures were the following: superficial layer, lateral retinaculum; intermediate layer, Lateral Collateral Ligament (LCL) and Lateral Patellofemoral Ligament (LPFL); deep layer, joint capsule. All of the knees examined presented a clearly distinguishable MPFL and LPFL separable from the capsular layer. Histological study: there was a higher density of nerve fibres in retinacula compared to ligaments (p = 0.0034) and a higher content of elastic fibres in retinacula (p < 0.0005). In imaging, there was no difference between medial and lateral retinaculum thickness (p > 0.05). In conclusion, both the lateral and medial compartment can be described using the three-layer scheme. PFLs and retinacula are separate structures both macroscopically and according to imaging analysis. The retinacula respond to their specific function with a higher nerve fibre content and higher number of elastic fibres compared to the ligaments.

Acute Compartment Syndrome Modeling with Sequential Infusion Shows the Deep Posterior Compartment Is Not Functionally Discrete

Clinical case series have indicated that 1 or 2-compartment decompression of the anterior or lateral leg may be sufficient for release, but, currently, no cadaveric model has verified that approach. The objective of this study was to investigate the functional relationship between compartments by alternating sequences of infusion and fasciotomy release. This study utilized multicompartment sequential pressurization with simultaneous monitoring by continuous pressure sensors to model compartment syndrome in a human cadaver leg. Subsequent sequential release of compartments and continuous streaming of pressure readings permitted unique insights. A leg model allowed the examination of pressure changes in all 4 compartments as treated with sequential fasciotomies. The successful modeling of lower-leg pressures consistent with compartment syndrome showed that discrepancies relative to accepted concepts were seen when the deep posterior compartment was pressurized in isolation. Also, release of 1 of the 2 of either the anterior or lateral compartments seems to be sufficient for decompression to acceptable pressure levels. The deep posterior compartment does not appear to be completely discrete and instead follows the pressurization curve of the posterior muscle group. This indicates that release of the deep posterior compartment may not be needed in all acute compartment syndrome scenarios. Surgical techniques can be modified for treatment of acute compartment syndrome to avoid large scar lengths, deep dissection, and multiple exposures that could improve patient outcomes.

Evolution of Somite Compartmentalization: A View From Xenopus.

Somites are transitory metameric structures at the basis of the axial organization of vertebrate musculoskeletal system. During evolution, somites appear in the chordate phylum and compartmentalize mainly into the dermomyotome, the myotome, and the sclerotome in vertebrates. In this review, we summarized the existing literature about somite compartmentalization in Xenopus and compared it with other anamniote and amniote vertebrates. We also present and discuss a model that describes the evolutionary history of somite compartmentalization from ancestral chordates to amniote vertebrates. We propose that the ancestral organization of chordate somite, subdivided into a lateral compartment of multipotent somitic cells (MSCs) and a medial primitive myotome, evolves through two major transitions. From ancestral chordates to vertebrates, the cell potency of MSCs may have evolved and gave rise to all new vertebrate compartments, i.e., the dermomyome, its hypaxial region, and the sclerotome. From anamniote to amniote vertebrates, the lateral MSC territory may expand to the whole somite at the expense of primitive myotome and may probably facilitate sclerotome formation. We propose that successive modifications of the cell potency of some type of embryonic progenitors could be one of major processes of the vertebrate evolution.

Predictive Factors for Skip Lymph Node Metastasis and Their Implication on Recurrence in Papillary Thyroid Carcinoma.

Skip lymph node (LN) metastases in papillary thyroid carcinoma (PTC) belong to N1b classification in the absence of central neck LN involvement. This study aimed to evaluate the predictive factors of skip metastases and their impact on recurrence in PTC patients with pN1b. A total of 334 PTC patients who underwent total thyroidectomy with LN dissection (central and lateral neck compartment) followed by radioactive iodine ablation were included. Patients with skip metastases tended to have a small primary tumor (≤1 cm) and single lateral neck level involvement. Tumor size ≤ 1 cm was an important predictive factor for skip metastases. Univariate analysis for recurrence showed that patients with a central LN ratio > 0.68, lateral LN ratio > 0.21, and stimulated thyroglobulin (Tg) levels > 7.3 ng/mL had shorter RFS (recurrence-free survival). The stimulated Tg level was associated with shorter RFS on multivariate analysis (>7.3 vs. ≤7.3 ng/mL; hazard ratio, 4.226; 95% confidence interval, 2.226−8.022; p < 0.001). Although patients with skip metastases tended to have a small primary tumor and lower burden of lateral neck LN involvement, there was no association between skip metastases and RFS in PTC with pN1b. Stimulated Tg level was a strong predictor of recurrence.

Radiographic vs. MRI vs. arthroscopic assessment and grading of knee osteoarthritis - are we using appropriate imaging?

PurposeRadiographs and MRI scans are commonly used imaging techniques in the assessment of knee osteoarthritis. However, it currently remains uncertain how good a representation of the actual condition of the knee joint these investigations provide. By comparing them against arthroscopic findings the aim of our study was to conclude how accurate these imaging techniques are at grading knee osteoarthritis.MethodsThis was a retrospective study looking at knee arthroscopies performed at a tertiary centre over a 5 year period. The Outerbridge grade given at arthroscopy was correlated with pre-operative radiograph and MRI scores, so as to assess the reliability of these imaging techniques at predicting the actual severity of knee osteoarthritis seen.ResultsKellgren-Lawrence (KL) grading of radiographs was moderately correlated with Outerbridge grades from arthroscopy for the medial compartment of the knee (Spearman’s rho (SR) 0.483, p < 0.001), with a milder correlation in the lateral compartment (SR 0.218, p = 0.003). MRI reporting of knee osteoarthritis was moderately correlated with Outerbridge grades in the medial compartment (SR 0.451, p < 0.001), mildly correlated for both the lateral (SR 0.299, p < 0.001) and patellofemoral joint compartments (SR 0.142, p = 0.054). KL and MRI grading was moderately correlated for the medial compartment (SR 0.475, p < 0.001) and mildly correlated for the lateral compartment (SR 0.277, p < 0.001).ConclusionThe ability of radiographs to represent the actual condition of knee osteoarthritis is underestimated. KL grading especially best represents the disease seen in the medial compartment of the knee joint, with a moderate correlation to Outerbridge scores given on arthroscopic assessment. We suggest that whilst MRI is a useful tool in the investigation of knee symptoms, it is often unnecessarily used in patients with OA, when in fact, radiographs alone would be sufficient.Evidence levelIII

LATERAL TIBIOFEMORAL 3‐D JOINT SPACE WIDTH AND BONE PARAMETERS IN COMBINATION ARE SIGNIFICANTLY RELATED TO PROGRESSION OF LATERAL AND MEDIAL COMPARTMENT JOINT SPACE NARROWING: A MULTICENTER OSTEOARTHRITIS STUDY INVESTIGATION

An important development in osteoarthritis imaging has been the ability to assess joint space width (JSW) from weight bearing CT (WBCT). The value of combining JSW with subchondral bone parameters in disease assessment is less well understood, particularly with respect to disease phenotype. To investigate associations of worsening medial and lateral tibiofemoral compartment structural disease over 2 years with a multivariate combination of baseline 3-D JSW and bony parameters from WBCT. WBCT knee imaging was acquired at the 144-month visit of the Multicenter Osteoarthritis Study along with same-visit and 2-year follow-up medial and lateral OARSI joint space narrowing (JSN) grade. After semi-automatic segmentation of 663 available knees, joint space mapping delivered 3-D JSW maps. Cortical bone mapping was performed to measure trabecular attenuation (TA), endocortical thickness (ET), and subchondral thickness (ST) at the femoral (f) and tibial (t) surfaces. A template was registered to each individual joint surface, a 3-D statistical shape model created, and all 7 spatially co-located parameters transferred to the template. A statistical parametric mapping (SPM) general linear model adjusted for age, sex, BMI, and the first 5 shape modes (controlling for effects of systematic misregistration) was used to test the dependence of JSW plus each bone parameter in turn on the experimental variables of 2-year medial and lateral OARSI JSN worsening. One knee per participant was used, selecting the side with greater JSN worsening, randomly if equal. 10 knees did not have radiographic grading, so the analysis used single knees from 394 individuals. 218 were female, mean ± SD age was 63.5 ± 9.6 years, mass 82.7 ± 17.7 kg, height 170 ± 9 cm, and BMI 28.5 ± 5.0 kg/m 2 . SPM results (figs 1-4 below) revealed significant parameter ROIs in the lateral tibiofemoral compartment that were associated with worsening of medial and lateral OARSI JSN grade at 2 years. Baseline lateral compartment JSW was significantly wider by up to ∼1 mm (unmasked lateral compartment blue zone in fig. 1) in combination with lower baseline tTA by up to ∼25 attenuation units (AU) (unmasked lateral compartment red zone in fig. 2) for each increment in future medial JSN over 2 years. The reverse was demonstrated for future lateral JSN with narrower baseline lateral JSW by up to ∼1 mm (unmasked lateral compartment red zone in fig. 3) in combination with higher baseline tTA by up to ∼25 AU (unmasked lateral compartment blue zone in fig. 4) for each grade of future lateral JSN over 2 years. Baseline JSW was significantly narrower at the lateral margin of the lateral compartment by up to ∼1 mm in combination with thicker tST and fST by up to ∼0.2 mm for each grade of future lateral JSN (not shown). Baseline medial 3-D JSW did not relate to any substantial significant future narrowing for any JSW-bone parameter combination for future medial or lateral JSN. ET results (with JSW) were very similar to those for ST at both sides of the joint. 3-D JSW analysed in combination with bone parameters at the lateral (but not medial) tibiofemoral compartment are significantly related to future medial and lateral OARSI JSN grade. Lower lateral compartment tTA (with higher JSW) is related to future medial JSN and may be an effect of trabecular remodelling from reduced lateral loading, while greater thickness of subchondral and endocortical bone in the lateral compartment (alongside lower JSW) can be explained by subchondral sclerosis. These results suggest the lateral compartment warrants closer attention for following both medial and lateral compartmental progression. National Institutes of Health, University of Kansas (R01AR071648), University of Iowa. (U01AG18832), University of California-San Francisco (U01AG19069), Boston University (U01AG018820). NS is a consultant for Integra BioLife, Trice Medical and Pacira Biosciences. The authors would like to thank participants and staff of the MOST study. CORRESPONDENCE ADDRESS: tom@turmezei.com .

NON-CHONDRAL MULTI-TISSUE PATHOLOGY AS ASSESSED BY MRI INCREASES RATES OF QUANTITATIVE MRI-DEFINED CARTILAGE THICKNESS LOSS OVER 24 MONTHS: THE APPROACH STUDY

NON-CHONDRAL MULTI-TISSUE PATHOLOGY AS ASSESSED BY MRI INCREASES RATES OF QUANTITATIVE MRI-DEFINED CARTILAGE THICKNESS LOSS OVER 24 MONTHS: THE APPROACH STUDY

Risk factors associated with the occurrence of total knee arthroplasty in patients with knee osteoarthritis: a nested case-control study.

Objectives:The aim of this study was to investigate changes over time in osteoarthritis risk factors most closely associated with the occurrence of total knee arthroplasty (TKA). We hypothesize that the robustness of a longitudinal case–control study will provide new information on the association between changes in various clinical and structural parameters in different time frames before TKA.Methods:Cases (195; TKA after cohort entry) and controls (468) matched for age, gender, income, WOMAC pain, Kellgren–Lawrence grade and follow-up duration were from the Osteoarthritis Initiative cohort. Associations between changes in sociodemographic, clinical, imaging and osteoarthritis therapies with the occurrence of TKA were performed using conditional logistic regression analyses.Results:Worsening of WOMAC scores (cOR 1.02–1.20, p ⩽ 0.012), KOOS (1.02–1.04, p ⩽ 0.014), knee injuries sustained in the previous 30–40 years (women 2.70, p = 0.034) and valgus alignment (1.10, p = 0.052) were associated with the occurrence of TKA. Also associated with TKA was cartilage volume loss in the lateral (overall 1.76, p = 0.025; women 1.93, p = 0.047) and medial compartments (⩾10%, overall 1.54, p = 0.027; men 2.34, p = 0.008), occurrence of medial meniscal extrusion (overall 1.77, p = 0.046; men 2.86, p = 0.028), and increase in bone marrow lesions (BMLs) for women (1.09, p = 0.048). The association of risk factors with TKA was reinforced when both an increase in WOMAC pain and cartilage volume loss (1.85, p = 0.001) were combined. Pain medication usage, mainly narcotics and intra-articular steroid injections (IASI), was also associated with TKA, with no impact on changes in cartilage loss or structure.Conclusion:This study provides new information about gender differences in risk factors associated with the occurrence of TKA. Worsening of valgus alignment, cartilage volume loss in the lateral compartment, BMLs and older injuries are important risk factors in women, while medial compartment cartilage loss and meniscal extrusion are in men. The use of pain medication and IASI although associated was found not causal with TKA.

Distally Based Peroneus Brevis Muscle Flap for Soft Tissue Reconstruction in Lower Third of Leg: A Case Series

Covering soft tissue defects in the distal part of leg and ankle is difficult. Most of the flaps used in reconstructing these defects are bulky and aesthetically unpleasing. The peroneus brevis muscle flap is ideal for covering these defects and providing an aesthetically better outcome. Peroneus brevis is a muscle located in the lateral compartment of the leg. It can be used for covering defects over the ankle and distal part of the leg without causing loss of function. This study was done to assess the surgical technique and clinical outcomes in the use of this muscle flap. This case series presents the authors’ experience of six cases of distally based peroneus brevis muscle flap. Three of the six patients were found to have superficial flap necrosis. Two of these three was treated with debridement and Split Skin Grafting (SSG) while one was managed conservatively with daily dressings. This flap is simple, easy to rise and useful in covering small defects of 3-4 cm width in the distal part of the leg and ankle. The donor site to be closed primarily leaving behind only a thin linear scar. Overtime the flap thins down and gives good cosmetic results. Donor site morbidity is minimal as the peroneus longus muscle is preserved and thus the function of the foot (plantar flexion and foot eversion) is intact. The distally based peroneus brevis flap is a reliable flap for covering defects over the distal one third of the leg, the upper half of the medial and lateral malleoli and the posterior aspect of the heel.

3-D JOINT SPACE WIDTH FROM WEIGHT BEARING COMPUTED TOMOGRAPHY IS BETTER THAN 2-D RADIOGRAPHIC MEASURES AT PREDICTING FUTURE LATERAL JOINT SPACE NARROWING AT THE KNEE: A MULTICENTER OSTEOARTHRITIS STUDY INVESTIGATION

3-D joint space width (JSW) measured from weight bearing CT (WBCT) has been suggested to be more sensitive than radiographic 2-D measurement in detecting joint space narrowing (JSN), but its diagnostic value in osteoarthritis is yet to be established. To determine the predictive validity of 3-D JSW measurement from baseline WBCT compared to 2-D radiographic measures in identifying structural disease progression at the knee. WBCT knee imaging was acquired at the 144-month visit of the Multicenter Osteoarthritis Study (MOST) with radiographic Kellgren and Lawrence grade (KLG), medial and lateral tibiofemoral radiographic OARSI JSN grades. Progression in medial and lateral JSN grade was recorded 2 years subsequent. After semi-automatic segmentation of 663 available knees, joint space mapping was performed to create 3-D JSW maps. A template was registered to each individual joint surface, a 3-D statistical shape model created, and JSW measurements transferred to the template. A statistical parametric mapping (SPM) general linear model adjusted for age, sex, BMI, and the first 5 shape modes (controlling for effects of systematic misregistration) was used to test the dependence of baseline 3-D JSW on baseline medial and lateral JSN in turn. One knee per participant was included in the SPM model, when required selecting side according to worst baseline compartmental JSN grade or randomly if equal. Mean JSW values from significantly narrower SPM ROIs were taken for all knees and used in receiver operating characteristic analysis to deliver areas under the curve (AUC) in a leave-one-out cross-validation classifier predictive model for future worsening of medial and lateral JSN at 2 years. This prediction model also tested baseline KLG, medial and lateral JSN grade. All predictive models were controlled by inclusion of age, sex, and BMI and compared against each other. 10 knees did not have radiographic grading, so the study set consisted of 653 knees from 394 individuals. 218 participants were female, mean ± SD age was 63.5 ± 9.6 years, mass 82.7 ± 17.7 kg, height 170 ± 9 cm, and BMI 28. 5 ± 5.0 kg/m 2 . SPM revealed regions of significantly narrower baseline medial JSW up to ∼0.75 mm per increment in medial JSN grade (unmasked medial compartment red zone in fig. 1) and narrower baseline lateral JSW up to ∼1 mm per increment in baseline lateral JSN grade (unmasked lateral compartment red zone in fig. 2). Mean medial and lateral ROI JSW values were taken at all available knees for predictive modelling. AUC values with 95% confidence limits showed that baseline mean medial ROI JSW (0.68, 0.61-0.74) was worse than baseline KLG (0.75, 0.68-0.81) and no better than medial JSN (0.73, 0.65-0.79) or lateral JSN (0.66, 0.6-0.71) in predicting future medial JSN. However, baseline mean lateral ROI JSW (0.84, 0.72-0.91) was better than medial JSN (0.61, 0.49-0.72) and lateral JSN (0.71, 0.54-0.86) in prediction of future lateral JSN. It was also better than baseline KLG (0.77, 0.76-0.86) but not outside the 95% confidence limits, however combining baseline lateral ROI JSW and KLG in the model further improved the AUC (0.87, 0.78-0.92) beyond the limits for just KLG (0.77, 0.76-0.86). Baseline 3-D lateral compartment JSW from WBCT is better than 2-D radiographic measures at predicting progression in lateral compartment JSN, but the same was not seen for medial JSN. This suggests an important role for 3-D weight bearing JSW in assessment of knee osteoarthritis according to disease phenotype. National Institutes of Health, University of Kansas (R01AR071648), University of Iowa (U01AG18832) and University of California-San Francisco (U01AG19069). NS is a consultant for Integra BioLife, Trice Medical and Pacira Biosciences. The authors would like to thank participants and staff of the MOST study. CORRESPONDENCE ADDRESS: tom@turmezei.com