Intraobserver and interobserver reliability of the computed tomography-based radiographic classification of primary elbow osteoarthritis: comparison with plain radiograph-based classification and clinical assessment

Anterior radial head subluxation in primary elbow osteoarthritis

PURPOSE

To investigate elbows with primary osteoarthritis (OA) for the presence of anterior radial head subluxation.

METHODS

A total of 71 patients with elbow osteoarthritis and 45 with lateral epicondylitis were initially identified. The baseline characteristics and preoperative elbow X-rays of consecutive patients that had been clinically confirmed with elbow OA or lateral epicondylitis between March 2011 and January 2020 were then retrospectively reviewed. The radiocapitellar ratio (RCR; the ratio of the displacement of the radial head about the diameter of the capitulum) was calculated using lateral views. These RCR values were compared between the OA and lateral epicondylitis cases.

RESULT

A significant increase was detected in RCR values between patients in elbow OA and the control group (13.2% (± 10.6) vs -1.2% (± 6.8), P<0.001). Based on receiver operating characteristic curves, RCR values had an excellent area under the curve (0.89) for the detection of elbow OA (Youden index, 0.69; sensitivity, 89%; specificity, 80%). Based on the ROC curve, the cutoff value of RCR was 0.04. Patients with RCR ≥ 0.04 had a significantly higher proportion of cases with elbow OA (risk ratio, 31.50 [95% CI, 11.17-88.82]) than those with RCR ˂ 0.04 (P ˂ 0.001).

CONCLUSION

Radial head subluxation is a radiographic finding associated with elbow OA and RCR ≥ 0.04 could be used as an aetiological factor for elbow OA diagnosis.

How Does the Subchondral Bone Density Distribution of the Distal Humerus Change Between Early and Advanced Stages of Osteoarthritis?

BACKGROUND

The distribution of subchondral bone density in a joint represents stress that is applied to the joint. Knowing this information is important for understanding the pathophysiology of osteoarthritis (OA). In the elbow, however, this has not been studied before.

QUESTIONS/PURPOSES

(1) Is advanced-stage elbow OA associated with more radially distributed subchondral bone density than earlier stages? (2) What demographic (age and sex) and radiographic (osteophyte location and carrying angle) factors are associated with increased radial shift in subchondral bone density?

METHODS

Between March 2001 and December 2021, we treated 301 patients for elbow OA. We considered patients with plain radiographs and conventional CT scans as potentially eligible. Thus, 68% (206 patients) were eligible; a further 27% (80 patients) were excluded because of a history of any injury or surgery or known inflammatory joint disease, leaving 42% (126 patients) for analysis here. Their mean ± standard deviation age was 60 ± 10 years. Early OA with minimal joint space narrowing and osteophyte formation was found in 33% (42 of 126) of patients, and advanced OA was found in the remaining 67% (84 of 126). Three-dimensional distal humerus subchondral bone models were derived from CT images, and in the central intra-articulating portion, we measured the subchondral bone density in two different sites: where it articulates with the radius (SBDrad) and with the ulna (SBDulna). We further defined the SBDratio as the percent ratio of SBDrad to SBDulna. We also evaluated osteophyte severity based on its size at the radiocapitellar and ulnotrochlear joints, and alignment through measuring the carrying angle on radiographs. To assess interobserver reliability, two orthopaedic surgeons took measurements independently from each other. All measurements had excellent intraoberver and interobserver reliabilities. Then, we compared the subchondral bone parameters between early and advanced OA and performed a multivariable analysis of the factors associated with subchondral bone parameters, including age, sex, osteophyte location, and carrying angle.

RESULTS

Radial versus ulna subchondral bone density (SBDratio) was modestly higher in patients with advanced OA (118% ± 17%) than in patients with early OA (109% ± 17%, mean difference 9% [95% CI 2.3% to 15.3%]; p = 0.01). With increasing radial deviation in subchondral bone density, cubitus valgus had a modest association (β = 0.46 ± 0.23; p = 0.04) and severe osteophytes at the radiocapitellar joint had a large association (β = 9.51 ± 3.06; p = 0.002).

CONCLUSION

According to subchondral bone density distribution, stress concentration was more radially deviated in patients with the advanced stages of elbow OA than in those with the early stages. We also found that an increase in carrying angle is associated with radial deviation of stress. A future study that examines longitudinal changes in the subchondral bone density might be required to confirm changes in stress concentration with OA progression.

CLINICAL RELEVANCE

This study gives us insight into the potential pathophysiology of elbow OA in relation to elbow alignment. Although debridement of osteophytes in the ulnotrochlear joint is the most frequently performed procedure in patients with advanced elbow OA, our finding suggests that some patients with an increased carrying angle might benefit from management of the radiocapitellar joint as well, or from being informed of the future development of OA in the radiocapitellar joint, because stress at this site can be increased with the advancement of OA.

Radiologically severe osteoarthritis is related to worse clinical outcomes after arthroscopic osteocapsular arthroplasty in primary elbow osteoarthritis at medium-term follow-up: a retrospective cohort study

HYPOTHESIS

This study aimed to compare the clinical outcomes after arthroscopic osteocapsular arthroplasty (OCA) at medium-term follow-up according to the radiologic severity of primary elbow osteoarthritis (OA) and assess serial changes in clinical outcomes in each group.

METHODS

Patients treated from January 2010 to April 2019 with arthroscopic OCA for primary elbow OA with a minimum of 3 years' follow-up were retrospectively assessed regarding range of motion (ROM), visual analog scale (VAS) pain score, and Mayo Elbow Performance Score (MEPS) preoperatively, at short-term follow-up (3-12 months postoperatively), and at medium-term follow-up (≥3 years after surgery). Preoperative computed tomography was performed to evaluate the radiologic severity of OA using the Kwak classification. Clinical outcomes were compared according to the radiologic severity of OA by their absolute values and the number of patients achieving the patient acceptable symptomatic state (PASS). Serial changes in the clinical outcomes in each subgroup were also assessed.

RESULTS

Of the 43 patients, 14, 18, and 11 were classified as the stage I, II, and III groups, respectively; the mean follow-up duration was 71.3 ± 28.9 months, and the mean age was 56.5 ± 7.2 years. At medium-term follow-up, the stage I group had a better ROM arc (stage I, 114° ± 14°; stage II, 100° ± 23°; and stage III, 97° ± 20°; P = .067) and VAS pain score (stage I, 0.9 ± 1.3; stage II, 1.8 ± 2.1; and stage III, 2.4 ± 2.1; P = .168) than the stage II and III groups without reaching statistical significance, whereas the stage I group had a significantly better MEPS (stage I, 93.2 ± 7.5; stage II, 84.7 ± 11.9; and stage III, 78.6 ± 15.2; P = .017) than the stage III group. The percentages of patients achieving the PASS for the ROM arc (P = .684) and VAS pain score (P = .398) were comparable between the 3 groups; however, the percentage achieving the PASS for the MEPS was significantly higher in the stage I group than in the stage III group (100.0% vs. 54.5%, P = .016). During serial assessment, all clinical outcomes tended to improve at the short-term follow-up. Compared with the short-term period, the ROM arc tended to decrease at the medium-term follow-up whereas the VAS pain score and MEPS overall did not show significant changes.

CONCLUSION

After arthroscopic OCA, the stage I group showed an overall better ROM arc and pain score than the stage II and III groups at medium-term follow-up, whereas the stage I group showed a significantly better MEPS and higher percentage of patients achieving the PASS for the MEPS than the stage III group.

Clinical Outcomes of Revision Arthroscopic Osteocapsular Arthroplasty in Primary Elbow Osteoarthritis: A Retrospective Cohort Study

BACKGROUND

Arthroscopic osteocapsular arthroplasty (OCA) achieves significant medium-term outcomes in patients with primary elbow osteoarthritis (OA); however, outcomes after revision arthroscopic OCA are not well known.

PURPOSE

To assess clinical outcomes after revision arthroscopic OCA as compared with those after primary surgery in patients with OA.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent arthroscopic OCA attributed to primary elbow OA between January 2010 and July 2020 were enrolled. Range of motion (ROM), visual analog scale (VAS) pain score, and Mayo Elbow Performance Score (MEPS) were assessed. Operation time and complications were assessed by chart review. Clinical outcomes between the primary and revision surgery groups were compared, and subgroup analysis for radiologically severe OA was performed.

RESULTS

Data from 61 patients were analyzed (primary, n = 53; revision, n = 8). The mean ± SD age was 56.3 ± 8.5 and 54.3 ± 8.9 years in the primary and revision groups, respectively. The primary group had significantly better ROM arcs preoperatively (89.9°± 20.3° vs 71.3°± 22.3°; P = .021) and postoperatively (112.4°± 17.1° vs 96.9°± 16.5°; P = .019) than the revision group; however, the degree of improvement was comparable (P = .445). Postoperative VAS pain score (P = .164) and MEPS (P = .581) were comparable between the groups, as were the degrees of improvement in VAS pain score (P = .691) and MEPS (P = .604). The revision group required a significantly longer operative time than the primary group (P = .004) and had a nonsignificant higher complication rate (P = .065). Subgroup analysis showed that radiologically severe cases in the primary group had significantly better preoperative (P = .010) and postoperative (P = .030) ROM arcs than the revision group and a comparable postoperative VAS pain score (P = .155) and MEPS (P = .658).

CONCLUSION

Revision arthroscopic OCA is a favorable treatment option for primary elbow OA with recurrent symptoms. Postoperative ROM arc was worse after revision surgery as compared with primary surgery; however, the degree of improvement was comparable. Postoperative VAS pain score and MEPS were comparable with primary surgery.

Ulnar nerve decompression with osteocapsular arthroplasty for primary elbow osteoarthritis

PURPOSE

The aim of this study was to suggest treatment guidline for primary elbow OA with ulnar nerve neuropathy or high-grade stiffness by evaluating the effect of ulnar nerve decompression on the outcome of osteocapsular arthroplasty.

METHODS

A total of 30 patients who underwent primary osteocapsular arthroplasty for elbow OA were retrospectively reviewed. The surgical outcomes were evaluated for pain score (visual analog scale; VAS), range of motion (ROM), and Mayo Elbow Performance Score (MEPS). The ulnar nerve decompression was performed for (1) ulnar nerve neuropathy, and (2) high-grade stiffness of flexion, defined as the flexion angle, is <90°. Patients were categorized into the two groups: ulnar nerve decompression group (UD group, n = 11) and the non-decompression group (Non-UD group, n = 19). The surgical outcome was compared between the groups.

RESULTS

Primary elbow OA with cubital tunnel syndrome or high-grade stiffness showed comparable improvement in MEPS, VAS, and ROM arc at final follow-up in the UD group compared with the non-UD group (UD group vs. non-UD group: MEPS 85.91 vs 86.84, p-value = 0.824, VAS 1.46 vs 1.16, p-value = 0.588, ROM arc 108 vs 109, p-value = 0.949). Improvement in ROM arc at 2 years follow-up was significantly higher in UD group (UD group vs. non-UD group: ROM arc difference, 42 vs 14, p = 0.002).

CONCLUSION

Osteocapsular arthroplasty with ulnar nerve decompression for primary elbow OA with ulnar nerve neuropathy or high-grade stiffness provided improved motion arc and compatible clinical results.

LEVEL OF EVIDENCE

Level III, Retrospective comparative study.

Development and validation of a prognostic nomogram for open elbow arthrolysis : the Shanghai Prediction model for Elbow Stiffness Surgical Outcome

AIMS

The aim of this study was to develop and internally validate a prognostic nomogram to predict the probability of gaining a functional range of motion (ROM ≥ 120°) after open arthrolysis of the elbow in patients with post-traumatic stiffness of the elbow.

METHODS

We developed the Shanghai Prediction Model for Elbow Stiffness Surgical Outcome (SPESSO) based on a dataset of 551 patients who underwent open arthrolysis of the elbow in four institutions. Demographic and clinical characteristics were collected from medical records. The least absolute shrinkage and selection operator regression model was used to optimize the selection of relevant features. Multivariable logistic regression analysis was used to build the SPESSO. Its prediction performance was evaluated using the concordance index (C-index) and a calibration graph. Internal validation was conducted using bootstrapping validation.

RESULTS

BMI, the duration of stiffness, the preoperative ROM, the preoperative intensity of pain, and grade of post-traumatic osteoarthritis of the elbow were identified as predictors of outcome and incorporated to construct the nomogram. SPESSO displayed good discrimination with a C-index of 0.73 (95% confidence interval 0.64 to 0.81). A high C-index value of 0.70 could still be reached in the interval validation. The calibration graph showed good agreement between the nomogram prediction and the outcome.

CONCLUSION

The newly developed SPESSO is a valid and convenient model which can be used to predict the outcome of open arthrolysis of the elbow. It could assist clinicians in counselling patients regarding the choice and expectations of treatment. Cite this article: Bone Joint J 2022;104-B(4):486-494.

Surgical management for primary osteoarthritis of the elbow

The objective of this review is to summarize the surgical options for primary osteoarthritis of the elbow, reported clinical outcomes, and suggested indications in previous literatures. The surgical management of primary elbow arthritis has evolved because of an improved understanding of pathologic mechanisms and manifestations as well as the development of novel surgical techniques and devices. Osteocapsular arthroplasty (OCA), elbow debridement, distraction arthroplasty, and total elbow arthroplasty (TEA) have been employed for managing elbow osteoarthritis. Elbow debridement and OCA can be helpful in most cases of symptomatic elbow arthritis. TEA is usually recommended for end-stage arthritis in elderly patients after prosthetic implants have been in place for long periods or after complications. Distraction arthroplasty might find a place in the treatment of younger, active patients with end-stage arthritis.

Primary Elbow Osteoarthritis: Evaluation and Management

Most patients with primary osteoarthritis of the elbow report a history of heavy lifting with the affected upper extremity . Conservative treatment, including activity modifications, nonsteroidal anti-inflammatory drugs and the occasional intraarticular corticosteroid injection, may provide adequate pain relief in earlier stages . When surgery is required, and despite the presence of cartilage wear, many patients with primary elbow osteoarthritis experience substantial pain improvement with joint preserving procedures . The ulnar nerve needs to be carefully assessed and addressed at the time of surgery . Although open debridement procedures are effective, arthroscopic osteocapsular arthroplasty has emerged as the surgical procedure of choice . Total elbow arthroplasty is very successful in terms of pain relief and function, but it is reserved for patients with end-stage osteoarthritis who are relatively older and have failed joint preserving procedures.

Arthroscopic osteocapsular arthroplasty for advanced-stage primary osteoarthritis of the elbow using a computed tomography-based classification

HYPOTHESIS

Arthroscopic osteocapsular arthroplasty for stage III osteoarthritis (advanced stage) shows worse clinical and radiologic outcomes compared with stage I or II according to computed tomography (CT)-based classification.

METHODS

Clinical and radiologic outcomes in 65 patients treated with arthroscopic osteocapsular arthroplasty were retrospectively analyzed for range of motion (ROM) arc, functional score (Mayo Elbow Performance Score [MEPS]), and pain score (visual analog scale [VAS]). Patients were classified into stage I or II (n = 44) and stage III (n = 21) groups according to CT-based classification, and postoperative clinical outcomes and complications were analyzed.

RESULTS

Mean follow-up duration was 32.9 ± 13.7 months (range, 24-69). The average patient age was 52 ± 10 years (range, 40-63). Improvements from preoperative to final follow-up were seen in the overall ROM-flexion from 94° ± 19° to 129° ± 14° (P < .01), ROM-extension from 25° ± 12° to 14° ± 7° (P < .01), MEPS from 45 ± 13 to 78 ± 14 (P < .01), and VAS score from 6.3 ± 1.6 to 3.1 ± 1.4 (P < .01). Subgroup analysis using the CT-based classification revealed that stage III led to worsened VAS score and MEPS than stage I or II.

CONCLUSIONS

Arthroscopic osteocapsular arthroplasty can be recommended for its favorable overall treatment outcomes for elbow osteoarthritis. However, stage III shows worse clinical and radiologic outcomes compared with stage I or II according to CT-based classification.