Diagnosing Systemic Amyloidosis Presenting as Carpal Tunnel Syndrome: A Risk Nomogram to Guide Biopsy at Time of Carpal Tunnel Release

Amyloidosis Screening by Biopsy During Carpal Tunnel Release: A Systematic Review and Meta-analysis

Background

Cardiac amyloidosis (CA) is an underdiagnosed cause of heart failure with newly available effective therapies. Carpal tunnel syndrome is a common early manifestation of amyloidosis, and tissue obtained during carpal tunnel release (CTR) can be screened for amyloid, allowing for early CA diagnosis and treatment. However, neither screening criteria nor diagnostic yield are well defined. We estimated the prevalence of amyloid within the tenosynovium or transverse carpal ligament and occult CA among patients undergoing screening biopsy during CTR based on the results of published studies.

Methods

We conducted a systematic review and meta-analysis of studies that analyzed screening biopsies obtained at the time of CTR for the presence of amyloid.

Results

Of 21 articles meeting inclusion criteria, 14 included biopsies from a general population undergoing CTR, 5 reported biopsies from a prescreened population at elevated risk for amyloidosis undergoing CTR, and 2 included patients undergoing CTR with suspected amyloidosis. The pooled prevalence of amyloid within the tenosynovium/transverse carpal ligament was 11% (95% confidence interval: 5%-18%) in American and European studies without prescreening, 20% (95% confidence interval: 13%-29%) in studies of screened patients, and 88%-100% in studies of patients suspected of having amyloidosis preoperatively. Overall, 5%-20% of patients with amyloid-positive biopsies who underwent cardiac screening were eventually diagnosed with CA, of whom 33% were started on transthyretin tetramer stabilizers.

Conclusions

Biopsies for amyloid during CTR demonstrate a high rate of positivity among at-risk populations and an opportunity for early detection of occult CA. Future studies should further refine diagnostic criteria to optimize cost-effectiveness of widespread screening.

American Academy of Orthopaedic Surgeons/ASSH Clinical Practice Guideline Summary Management of Carpal Tunnel Syndrome

Management of Carpal Tunnel Syndrome Evidence-Based Clinical Practice Guideline is based on a systematic review of published studies with regard to the diagnosis and treatment of carpal tunnel syndrome in adult patients (≥18 years of age). The scope of this guideline addresses the diagnosis and treatment of carpal tunnel syndrome and contains nine recommendations to assist orthopaedic surgeons and all qualified clinicians managing patients presenting with signs and symptoms which may be attributable to carpal tunnel syndrome based on the best current available evidence. It is also intended to serve as an information resource for professional healthcare practitioners, health services researchers, and developers of practice guidelines and recommendations. In addition to providing pragmatic practice recommendations, this guideline also highlights gaps in the literature and informs areas for future research and quality measure development.

Occult Amyloid Deposition in Older Patients Presenting With Bilateral Carpal Tunnel Syndrome or Multiple Trigger Digits

PURPOSE

The diagnosis of amyloidosis is important for early intervention, disease monitoring, and prevention of complications and progression. Carpal tunnel syndrome (CTS) and trigger digit (TD) are two common conditions associated with early disease. The purpose of this study was to define disease prevalence among patients with bilateral CTS and multiple TDs and assess for an increased rate of diagnosis in the presence of both.

METHODS

Men older than 50 years and women older than 60 years of age diagnosed with bilateral CTS, multiple TDs, or a combination of the 2 were prospectively enrolled in our study. Tenosynovial biopsy samples taken at the time of surgery were tested for the presence of amyloid using Congo red staining. Demographic and medical covariates were also collected and analyzed for differences between amyloid-positive and -negative patients.

RESULTS

Fifty-six patients were enrolled in the study, and nine patients tested positive for amyloid deposition. The demographics and medical comorbidities were similar between amyloid-positive and -negative patients. Thirty patients with bilateral CTS were enrolled, and four tested positive for amyloid. For patients with multiple TDs, a total of 17 patients were enrolled, and 4 tested positive for amyloid. Among patients with multiple TDs, only men tested positive for amyloid and were, on average, younger than those who tested negative (61 and 73 years, respectively). Patients presenting with a combination of CTS and TD did not exhibit increased amyloid discovery.

CONCLUSIONS

Hand surgeons should consider tenosynovial biopsy in men older than 50 years and women older than 60 years presenting with either bilateral CTS or multiple TDs.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Amyloidosis and carpal tunnel syndrome: can we predict occurrence?

INTRODUCTION

Carpal tunnel syndrome, especially when bilateral, may be associated with amyloid deposits, a precursor of systemic amyloidosis. Systemic amyloidosis affects various organs, cardiac involvement having the poorest prognosis. Diagnosis is often delayed. Current treatments are only effective in the early stages of the disease. The primary objective of our study was to evaluate the incidence of amyloidosis in patients with bilateral carpal tunnel syndrome; the secondary aim was to screen for cardiac forms.

MATERIAL AND METHODS

Between 2019 and 2023, we conducted a single-center prospective observational and diagnostic study to investigate the anatomical pathology of amyloid deposits in tenosynovial samples taken during open nerve release surgery on the median nerve. The tenosynovial biopsy was sent to a specific laboratory for analysis, and typing if positive. If amyloidosis was detected, the patient was referred to a specialist for a specific work-up.

RESULTS

We included 54 patients, with a mean age of 67 years (range, 51-89 years): 16 men and 38 women. Sixteen analyses were positive, 12 of which were transthyretin and 4 non-typed.

DISCUSSION/CONCLUSION

Bilateral carpal tunnel syndrome was predictive of amyloidosis. As synovial biopsy during surgery is simple and rapid, it should be implemented to identify amyloidosis at an early stage. This could change prognosis, by improving survival through screening and initiation of early specific treatment.

LEVEL OF EVIDENCE

IV.

Exploring the Utility of Carpal Tunnel Biopsy in Amyloidosis: A Current Perspective

Recent literature has emphasized the role of hand surgeons in screening patients with carpal tunnel syndrome (CTS) for amyloidosis by performing a carpal tunnel synovial biopsy during open carpal tunnel release (CTR). This has led to misconceptions about the diagnostic utility of synovial biopsy and the clinical evaluation of suspected amyloidosis. Controversy over carpal tunnel biopsy is exacerbated by minimally invasive advances in CTR procedures. This current perspective aims to determine the role of carpal tunnel synovial biopsy in amyloidosis and provide an update for hand surgeons regarding the nuances of amyloidosis. We conclude that carpal tunnel synovial biopsy should not be performed without CTS symptoms but only in patients meeting criteria for open CTR such as in those with severe symptoms which have failed nonoperative treatment and minimally invasive procedures are contraindicated. A screening approach for amyloidosis is proposed in patients presenting with CTS symptoms. Despite advances in the understanding, treatment, and diagnosis of amyloidosis, there remains a need for accurate, specific, and sensitive diagnostic tests.

Early Diagnosis and Treatment of Cardiac Amyloidosis by Screening Biopsy During Trigger Finger Release

Patients undergoing trigger release surgery are known to be at increased risk of amyloidosis and heart failure, and therefore, amyloidosis screening during trigger release surgery may facilitate early diagnosis and treatment of cardiac amyloidosis. However, the reported prevalence of amyloid on biopsies taken during trigger release surgery has varied widely, and no biopsy-positive patients in prior studies have been diagnosed with occult cardiac amyloidosis or started on disease-modifying therapy. We review the existing literature on this topic and present a case of a patient with cardiac amyloidosis diagnosed from a biopsy taken during trigger release surgery and subsequently started on disease-modifying therapy. This case supports the potential role of amyloidosis screening during trigger release and highlights the benefits of collaboration between hand surgeons and amyloidosis specialists in multidisciplinary amyloidosis programs.

Prevalence of transthyretin amyloidosis in patients undergoing carpal tunnel surgery: a prospective cohort study and risk factor analysis

Transthyretin amyloidosis is a frequent cause of heart failure, resulting from an accumulation of abnormal proteins in the myocardium. Recent research has highlighted the importance of early diagnosis to enhance the effectiveness of specific treatments. Extra-cardiac symptoms may precede several years before cardiac complications, with carpal tunnel syndrome often considered a red flag. The aim of this prospective, observational cohort study was to determine the incidence rate of positive synovial biopsies for transthyretin amyloidosis in patients aged 60-80 years undergoing carpal tunnel decompression, and to identify risk factors. The diagnosis of transthyretin amyloidosis was confirmed through the analysis of synovial tissue biopsies using Congo Red and immunohistochemical staining. The study included 254 patients, with an 18.5% prevalence of transthyretin amyloidosis. Risk factors for positive test results were identified as male sex, trigger finger, hearing disorders and valve disease. A predictive analysis using logistic regression yielded a probability model for individuals belonging to the positive group.Level of evidence III.

Results of Implementation of Amyloidosis Screening for Patients Undergoing Carpal Tunnel Release

PURPOSE

Many patients with amyloidosis undergo carpal tunnel release (CTR) before amyloidosis diagnosis and before developing cardiac or other serious disease manifestations. The purposes of this study were to examine if our patient population had a similar prevalence of positive amyloidosis diagnoses to that in prior studies and to describe the results of implementing a screening program for amyloidosis.

METHODS

We retrospectively reviewed the biopsy results and subsequent interventions for all patients who underwent screening tenosynovial biopsy during CTR from March 2020 through December 2021. Amyloid screening was offered to patients who met the criteria for increased risk of disease using an appropriateness screening algorithm.

RESULTS

Seventy-five (48%) of 156 patients who underwent CTR met the eligibility criteria for amyloidosis testing. Of the 62 patients who agreed to undergo tenosynovial biopsy, 14 had amyloid-positive biopsy specimens (10 men and 4 women). All patients with positive tenosynovial biopsies had bilateral carpal tunnel syndrome and wild-type transthyretin amyloid subtype. One patient was diagnosed and started treatment for otherwise asymptomatic cardiac amyloidosis.

CONCLUSIONS

The incidence of amyloid-positive tenosynovial biopsy results from CTR was 22.5% in patients using the criteria from an appropriateness screening algorithm, which was higher than previously reported. Implementation of a screening program for patients undergoing CTR requires a multidisciplinary approach and may result in early diagnosis and lifesaving interventions for patients with amyloidosis.

TYPE OF STUDY/LEVEL OF EVIDENCE

Differential diagnosis/symptom prevalence study, II.

Being a Better Starfish Thrower, Carpal Tunnel Syndrome, and Cardiac Amyloidosis: The Hand Surgeon's Opportunity to Make a Profound Difference

In recent years, there is increasing literature in cardiac and hand surgery journals demonstrating a stronger association between seemingly idiopathic carpal tunnel and amyloidosis. Despite this, it can be difficult for hand surgeons to identify who need biopsies, and this is further complicated by the cost of a biopsy and the low likelihood that a patient has cardiac amyloidosis. In patients with cardiac amyloidosis and carpal tunnel syndrome (CTS), CTS is typically diagnosed 5-10 years prior. Early diagnosis of cardiac amyloidosis is crucial, as current medications work to slow disease progression, but do not treat existing amyloid deposits. Hand surgeons can play an essential role in early diagnosis. The patient case discussed describes a man who had a carpal tunnel biopsy because of his bilateral CTS, recurrent trigger fingers, and his age. After confirmation of amyloidosis, he was referred for cardiac amyloidosis evaluation. Testing confirmed this diagnosis, and he was started on tafamidis, which studies show provide patients an opportunity for increased survival and quality of life. The responsibility falls on cardiologists and hand surgeons to continue refining the indications for carpal tunnel biopsy and spreading awareness of carpal tunnel biopsy and amyloid testing, as much work is still needed.

Amyloidosis and Considerations for the Hand Surgeon

Amyloidosis can lead to cardiac, renal, and other multiorgan failure. New treatments have become available that can prolong survival but rely on early diagnosis. Manifestations of amyloidosis in hand surgery include carpal tunnel syndrome, trigger finger, peripheral neuropathy, and spontaneous distal biceps rupture. Often, these can predate systemic amyloidosis, offering hand surgeons an opportunity to diagnose patients with amyloidosis before systemic disease, refer them for treatment, and potentially alter disease course and prolong survival. In this review, we describe the pathophysiology and two most common subtypes of amyloidosis seen by hand surgeons. We provide guidance on biopsy practices and referral for patients with amyloidosis. Lastly, we provide a brief overview of the treatments for amyloidosis and their effect on disease course.

Revision Carpal Tunnel Release Following Endoscopic Compared With Open Decompression

Importance

Carpal tunnel release (CTR) technique may influence the likelihood of revision surgery. Prior studies of revision CTR following endoscopic CTR (ECTR) compared with open CTR (OCTR) have been limited by sample size and duration of follow-up.

Objective

To estimate the incidence of revision CTR following ECTR compared with OCTR in a national cohort.

Design, Setting, and Participants

This retrospective cohort study used data from the US Veterans Health Administration. Participants included all adults (age ≥18 years) undergoing at least 1 outpatient CTR from October 1, 1999, to May 20, 2021. Data were analyzed from May 21, 2021, to November 27, 2023.

Exposure

Index CTR technique.

Main Outcomes and Measures

The primary outcome was time to revision CTR, defined as repeat ipsilateral CTR during the study period. Secondary outcomes were indications for revision, findings during revision, and additional procedures performed during revision.

Results

Among 134 851 wrists from 103 455 patients (92 510 [89.4%] male; median [IQR] age, 62 [53-70] years) undergoing at least 1 CTR, 1809 wrists underwent at least 1 revision at a median (IQR) of 2.5 (1.0-3.8) years. In competing-risks analysis, the cumulative incidence of revision was 1.06% (95% CI, 0.99%-1.12%) at 5 years and 1.59% (95% CI, 1.51%-1.67%) at 10 years. ECTR was associated with increased hazard of revision CTR compared with OCTR (adjusted hazard ratio [aHR], 1.56; 95% CI, 1.34-1.81; P < .001). The risk difference for revision CTR associated with ECTR compared with OCTR was 0.57% (95% CI, 0.31%-0.84%) at 5 years (number needed to harm, 176) and 0.72% (95% CI, 0.36%-1.07%) at 10 years (number needed to harm, 139). Regardless of index CTR technique, the most common indication for revision was symptom recurrence (1062 wrists [58.7%]). A reconstituted transverse carpal ligament (TCL) was more common after ECTR compared with OCTR, whereas scarring of the overlying tissues and of the median nerve itself were more common following OCTR. Incomplete transverse-carpal-ligament release was observed in 251 of the wrists undergoing revision CTR (13.94%) and was more common among revisions following ECTR (odds ratio, 1.62; 95% CI, 1.11-2.37; P = .01).

Conclusions and Relevance

In this cohort study of revision CTR in the Veterans Health Administration, ECTR was associated with increased risk of revision compared with OCTR, but the absolute risk was low regardless of technique. Intraoperative findings at revision varied significantly according to index CTR technique.

Musculoskeletal manifestations associated with transthyretin-mediated (ATTR) amyloidosis: a systematic review

BACKGROUND

Hereditary and wild-type transthyretin-mediated (ATTRv and ATTRwt) amyloidoses result from the misfolding of transthyretin and aggregation of amyloid plaques in multiple organ systems. Diagnosis of ATTR amyloidosis is often delayed due to its heterogenous and non-specific presentation. This review investigates the association of musculoskeletal (MSK) manifestations with ATTR amyloidosis and the delay from the onset of these manifestations to the diagnosis of ATTR amyloidosis.

METHODS

This systematic review utilized Medline and EMBASE databases. Search criteria were outlined using a pre-specified patient, intervention, comparator, outcome, time, study (PICOTS) criteria and included: amyloidosis, ATTR, and MSK manifestations. Publication quality was assessed utilizing Joanna Briggs Institute (JBI) critical appraisal checklists. The search initially identified 7,139 publications, 164 of which were included. PICOTS criteria led to the inclusion of epidemiology, clinical burden and practice, pathophysiology, and temporality of MSK manifestations associated with ATTR amyloidosis. 163 publications reported on ATTR amyloidosis and MSK manifestations, and 13 publications reported on the delay in ATTR amyloidosis diagnosis following the onset of MSK manifestations.

RESULTS

The MSK manifestation most frequently associated with ATTR amyloidosis was carpal tunnel syndrome (CTS); spinal stenosis (SS) and osteoarthritis (OA), among others, were also identified. The exact prevalence of different MSK manifestations in patients with ATTR amyloidosis remains unclear, as a broad range of prevalence estimates were reported. Moreover, the reported prevalence of MSK manifestations showed no clear trend or distinction in association between ATTRv and ATTRwt amyloidosis. MSK manifestations precede the diagnosis of ATTR amyloidosis by years, and there was substantial variation in the reported delay to ATTR amyloidosis diagnosis. Reports do suggest a longer diagnostic delay in patients with ATTRv amyloidosis, with 2 to 12 years delay in ATTRv versus 1.3 to 1.9 years delay in ATTRwt amyloidosis.

CONCLUSION

These findings suggest that orthopedic surgeons may play a role in the early diagnosis of and treatment referrals for ATTR amyloidosis. Detection of MSK manifestations may enable earlier diagnosis and administration of effective treatments before disease progression occurs.

Clinical characteristics and prognostic implications of orthopedic ligament disorders in patients with wild-type transthyretin amyloidosis cardiomyopathy

BACKGROUND

Wild-type transthyretin amyloidosis (ATTRwt) is associated with multiple ligament disorders (LD) such as carpal tunnel syndrome (CTS), lumbar spinal stenosis (LSS), and spontaneous tendon rupture (STR). No studies have investigated the prevalence of these LD in the same cohort of ATTRwt patients. Furthermore, the clinical characteristics and prognostic implications of such disorders have not been studied.

METHODS

From 2017 to 2022, 206 consecutive patients with ATTRwt were diagnosed and followed prospectively to the time of death or the censoring date of September 1st, 2022. Patients with and without LD were compared, and the presence of LD was used along with the baseline clinical, biochemical, and echocardiographic characteristics to predict hospitalization with worsening heart failure and death.

RESULTS

CTS surgery was performed in 34 % of the patients, 8 % were treated for LSS, and 10 % had experienced an STR. The median follow-up time was 706 days (312-1067). Hospitalization with worsening heart failure occurred more frequently in patients with LD compared to patients without LD (p = 0.035). Presence of LD or surgery for CTS were found to be independent predictors of worsening heart failure with a hazard ratio of 2.0 (p = 0.01). The mortality was comparable between patients with and without LD (p = 0.10).

CONCLUSION

Orthopedic disorders are prevalent in ATTRwt cardiomyopathy, and presence of LD was an independent predictor of hospitalization with worsening heart failure.

Amyloidosis and Carpal Tunnel Syndrome: Surgical Technique for Extended Carpal Tunnel Release with Tenosynovium and Transverse Carpal Ligament Biopsies

Carpal tunnel syndrome (CTS) is common in patients with transthyretin amyloidosis (ATTR), and many experience residual symptoms and/or develop recurrent disease following routine carpal tunnel release (CTR). An extended CTR with median nerve neurolysis is recommended for thorough nerve decompression. Tissue confirmation of amyloidosis can be performed at the time of CTR with biopsies of the transverse carpal ligament and/or tenosynovium.

METHODS

We describe a retrospective, single-center experience performing an extended CTR technique including unilateral and bilateral cases for 13 consecutive patients (18 wrists) with ATTR and symptomatic median neuropathy at the wrist.

RESULTS

The mean patient age was 83 (range 67-90) years and 11 (85%) were men. Notable intraoperative findings in all cases included thickened tenosynovium and median nerve epineurium, and adherence of the median nerve to the deep surface of transverse carpal ligament. Pathology findings were positive for amyloidosis from both the transverse carpal ligament and the tenosynovium biopsies in all patients.

CONCLUSIONS

Extended CTR with simultaneous wrist tissue biopsy can be safely performed for ATTR patients with CTS. Characteristic intraoperative findings should increase clinical suspicion for undiagnosed ATTR and prompt performance of biopsy for diagnostic confirmation. Volar wrist tenosynovial biopsy is our preferred tissue for confirmation of ATTR, for patients with and without CTS, given its safety profile and 100% pathological yield in our series.

Identification of wild-type transthyretin cardiac amyloidosis in patients with carpal tunnel syndrome surgery (CACTuS)

AIMS

Wild-type transthyretin cardiac amyloidosis (ATTRwt) is an infiltrative cardiomyopathy with a poor prognosis. The condition is associated with carpal tunnel syndrome (CTS), which often precedes the ATTRwt diagnosis by several years. The aim of the study was (i) to screen patients with a recent history of CTS for ATTRwt using red flags, (ii) to determine whether patients with screened ATTRwt had less advanced disease compared with patients with clinical ATTRwt, and (iii) to assess the sensitivity and specificity of known red flags in ATTRwt.

METHODS AND RESULTS

Patients aged ≥60 years at the time of CTS surgery were invited for screening. Red flags were defined as elevated biomarker levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) or cardiac troponin, an electrocardiogram pattern associated with ATTRwt, left ventricular hypertrophy (LVH), and impaired longitudinal strain with apical sparring. All patients with a red flag were referred for a diagnostic scintigraphy. Patients with ATTRwt diagnosed by screening were compared with patients with clinical ATTRwt (n = 51) matched by age, gender, and CTS surgery. Among the 120 enrolled subjects (mean age 74.5 years, 90% male), the suspicion of ATTR was raised in 67 (55.8%), and 10 (8.3%) were diagnosed with ATTRwt. Patients identified with ATTRwt were predominantly asymptomatic and had mildly elevated NT-proBNP, mildly increased LVH, preserved left ventricular ejection fraction, and systolic longitudinal function, which differed significantly from clinical ATTRwt controls (P < 0.001).

CONCLUSIONS

The study found an ATTRwt prevalence of 8.3% in a population of age and gender-selected patients with a recent history of CTS. The identified patients with ATTRwt had less structural and functional cardiac involvement than clinical ATTRwt controls.

Evaluation of strain echocardiography and atrial electromechanical delay in patients with idiopathic carpal tunnel syndrome

Aim: Carpal tunnel syndrome (CTS) could be an early marker for amyloidosis before developing of overt symptoms of cardiac amyloidosis (CA). CA characterized with left ventricular (LV) diastolic dysfunction and impairment of LV deformation-based parameters. There is limited data about echocardiographic parameters such as strain value of LV, diastolic parameters and atrial EMD in patients with idiopathic CTS. In this study, we investigated LV strain values, diastolic parameters of LV and atrial EMD in patients with idiopathic CTS. Then, we compared these parameters in CTS patients to control group. Material and Method: Thirty-four patients with idiopathic CTS and twenty-four aged and sex matched volunteers were enrolled to study. Patients with known amyloidosis, heart failure, diabetes mellitus and secondary etiologic states for CTS such as trauma or rheumatologic disease were excluded from the study. ECG and echocardiographic examination of each patient were performed and recorded by cardiology specialist. Conventional and strain imaging echocardiography were performed. Atrial electromechanical delays (EMD) were measured. Results: Baseline characteristics features were not different in groups. Mitral inflow velocities (mitral E and A wave), mitral E wave deceleration time, tissue Doppler velocities (lateral annular E’ and A wave), E/A and E/E’ ratios were similar in two groups. Septal basal strain values increased in CTS group (-21.3±4.83% vs -25.7±2.96%, p&lt;0.001). Septal apical to base ratio (SAB) and relative apical sparing (RELAPS) were increased in CTS group compared to control group (0.94±0.43 vs 0.66±0.12, 0.90±0.31 vs 0.73±0.08, p=0.004, p=0.013, respectively). PA lateral, PA septal, inter-atrial EMD and intra-atrial EMD were significantly higher in CTS group compared to control group (78.2±12.3 ms vs 70.6±9.9 ms, 64.1±8.42 ms vs 58.3±10.1 ms, 25.8±9.09 ms vs 20.7±5.31 ms, 11.68±5.11 ms vs 8.46±3.02 ms, p=0.015, p=0.023, p=0.009 and p=.008, respectively). Conclusion: In CTS group, mean basal strain decreased compared to control group. SAB and RELAPS which associate with CA, decreased in CTS group. Atrial EMD prolonged in CTS group. These changes may associate with increased risk of CA and AF in patients with CTS.

Cervical amyloidoma of transthyretin type: a case report and review of literature

Background

Amyloidoma is a rare clinical entity characterized by the focal aggregation of amyloid protein within the body, void of systemic involvement. To our knowledge, there have only been 26 reports of cervical amyloidoma to date. Amyloid light chain and beta-2-microglobulin are the most common types, with only three previous reports of transthyretin (ATTR) Amyloidoma.

Case presentation

We report a case of a 71-year-old male who presented with worsening strength and coordination of his upper extremities, right upper-leg pain, unsteady gait, and a reduced range of motion of his neck in all planes. Magnetic resonance imaging revealed a solitary mass compressing the spinal cord at C1-C2. Treatment consisted of cervical decompression and stabilization. Pathological examination confirmed solitary amyloid deposition of ATTR. Postoperative neurological assessment revealed improved balance, gait, hand function, and grip strength. Investigational imaging was ordered 8 months postoperatively revealing no evidence of systemic involvement, confirming the diagnosis of cervical ATTR amyloidoma. A discussion is provided surrounding the published literature of ATTR amyloidoma with description of the typical presentation, management, and outcomes of this rare pathology.

Conclusion

Previous cases and studies indicate clinical signs such as ligamentum of flavum hypertrophy and carpal tunnel syndrome may precede focal ATTR spinal disposition. Outcomes for amyloidoma are generally favourable, as tumour resection prevents irreversible deficits. Patients have a low rate of recurrence with an overall excellent prognosis following resection and stabilization.

A new prognostic nomogram for heterotopic ossification formation after elbow trauma : the Shanghai post-Traumatic Elbow Heterotopic Ossification Prediction (STEHOP) model

AIMS

Heterotopic ossification (HO) is a common complication after elbow trauma and can cause severe upper limb disability. Although multiple prognostic factors have been reported to be associated with the development of post-traumatic HO, no model has yet been able to combine these predictors more succinctly to convey prognostic information and medical measures to patients. Therefore, this study aimed to identify prognostic factors leading to the formation of HO after surgery for elbow trauma, and to establish and validate a nomogram to predict the probability of HO formation in such particular injuries.

METHODS

This multicentre case-control study comprised 200 patients with post-traumatic elbow HO and 229 patients who had elbow trauma but without HO formation between July 2019 and December 2020. Features possibly associated with HO formation were obtained. The least absolute shrinkage and selection operator regression model was used to optimize feature selection. Multivariable logistic regression analysis was applied to build the new nomogram: the Shanghai post-Traumatic Elbow Heterotopic Ossification Prediction model (STEHOP). STEHOP was validated by concordance index (C-index) and calibration plot. Internal validation was conducted using bootstrapping validation.

RESULTS

Male sex, obesity, open wound, dislocations, late definitive surgical treatment, and lack of use of non-steroidal anti-inflammatory drugs were identified as adverse predictors and incorporated to construct the STEHOP model. It displayed good discrimination with a C-index of 0.80 (95% confidence interval 0.75 to 0.84). A high C-index value of 0.77 could still be reached in the internal validation. The calibration plot showed good agreement between nomogram prediction and observed outcomes.

CONCLUSION

The newly developed STEHOP model is a valid and convenient instrument to predict HO formation after surgery for elbow trauma. It could assist clinicians in counselling patients regarding treatment expectations and therapeutic choices. Cite this article: Bone Joint J 2022;104-B(8):963-971.

Risk of Amyloidosis and Heart Failure Among Patients Undergoing Surgery for Trigger Digit or Carpal Tunnel Syndrome: A Nationwide Cohort Study With Implications for Screening

PURPOSE

Tenosynovial biopsy during carpal tunnel release (CTR) leads to an earlier diagnosis of amyloidosis. Surgery for trigger digit-trigger release (TR)-may provide a similar opportunity. We sought to characterize the risk of amyloidosis diagnosis after TR and/or CTR.

METHODS

We conducted a retrospective cohort study of adults without diagnosed amyloidosis undergoing TR and/or CTR in the Veterans Health Administration from 1999 to 2019, including matched controls. We used competing-risks methodology to estimate the cumulative incidence and adjusted subdistribution hazard ratios (sHRs) of amyloidosis, heart failure, and death after TR and/or CTR.

RESULTS

Among the 126,788 patients undergoing TR and/or CTR, amyloidosis was diagnosed in 52 of 26,757 patients undergoing TR alone at a median of 4.7 years after surgery (10-year cumulative incidence: 0.26%, 95% CI: 0.18% to 0.34%), 396 of 91,384 patients undergoing CTR alone at a median of 5.1 years after surgery (10-year cumulative incidence: 0.60%, 95% CI: 0.53% to 0.67%), 50 of 8,647 patients undergoing both TR and CTR at a median of 3.1 years after surgery (10-year cumulative incidence: 0.80%, 95% CI: 0.54% to 1.1%), and 54 of 113,452 controls at a median of 5.0 years after the index date (10-year cumulative incidence 0.053%, 95% CI: 0.037% to 0.070%). In the adjusted analysis, patients who underwent TR and/or CTR had a higher risk of amyloidosis (TR: sHR_adj 4.80, 95% CI: 3.33-6.92; CTR: sHR_adj 10.2, 95% CI: 7.74-13.6; TR and CTR: sHR_adj 14.9, 95% CI: 9.87-22.5) and heart failure (TR: sHR_adj 1.91, 95% CI: 1.83-1.99; CTR: sHR_adj 2.02, 95% CI: 1.97-2.07; TR and CTR: sHR_adj 2.18, 95% CI: 2.04-2.33) but not death compared with the controls. Among the patients who underwent TR, age, Black race, prior CTR, heart failure, and the number of digits released were independent risk factors for amyloidosis.

CONCLUSIONS

Patients undergoing TR and/or CTR are at increased risk of incident amyloidosis and heart failure compared to controls.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Suspicion, screening, and diagnosis of wild-type transthyretin amyloid cardiomyopathy: a systematic literature review

Wild-type transthyretin amyloid cardiomyopathy (ATTRwt CM) is a more common disease than previously thought. Awareness of ATTRwt CM and its diagnosis has been challenged by its unspecific and widely distributed clinical manifestations and traditionally invasive diagnostic tools. Recent advances in echocardiography and cardiac magnetic resonance (CMR), non-invasive diagnosis by bone scintigraphy, and the development of disease-modifying treatments have resulted in an increased interest, reflected in multiple publications especially during the last decade. To get an overview of the scientific knowledge and gaps related to patient entry, suspicion, diagnosis, and systematic screening of ATTRwt CM, we developed a framework to systematically map the available evidence of (i) when to suspect ATTRwt CM in a patient, (ii) how to diagnose the disease, and (iii) which at-risk populations to screen for ATTRwt CM. Articles published between 2010 and August 2021 containing part of or a full diagnostic pathway for ATTRwt CM were included. From these articles, data for patient entry, suspicion, diagnosis, and screening were extracted, as were key study design and results from the original studies referred to. A total of 50 articles met the inclusion criteria. Of these, five were position statements from academic societies, while one was a clinical guideline. Three articles discussed the importance of primary care providers in terms of patient entry, while the remaining articles had the cardiovascular setting as point of departure. The most frequently mentioned suspicion criteria were ventricular wall thickening (44/50), carpal tunnel syndrome (42/50), and late gadolinium enhancement on CMR (43/50). Diagnostic pathways varied slightly, but most included bone scintigraphy, exclusion of light-chain amyloidosis, and the possibility of doing a biopsy. Systematic screening was mentioned in 16 articles, 10 of which suggested specific at-risk populations for screening. The European Society of Cardiology recommends to screen patients with a wall thickness ≥12 mm and heart failure, aortic stenosis, or red flag symptoms, especially if they are >65 years. The underlying evidence was generally good for diagnosis, while significant gaps were identified for the relevance and mutual ranking of the different suspicion criteria and for systematic screening. Conclusively, patient entry was neglected in the reviewed literature. While multiple red flags were described, high-quality prospective studies designed to evaluate their suitability as suspicion criteria were lacking. An upcoming task lies in defining and evaluating at-risk populations for screening. All are steps needed to promote early detection and diagnosis of ATTRwt CM, a prerequisite for timely treatment.

Prevalence and Subtypes of Tenosynovial Amyloid in Patients Undergoing Carpal Tunnel Release

PURPOSE

The purpose of this study was to determine the prevalence and subtypes of amyloid in tenosynovial biopsies of patients undergoing carpal tunnel release (CTR).

METHODS

A retrospective review was performed involving patients who underwent CTR from June 2020 to July 2021. Prior to this period, a protocol had been established to obtain routine intraoperative tenosynovial biopsies. Tenosynovium was preserved in formalin and stained with Congo red for amyloid. Positive specimens were sent to an external laboratory for confirmation and subtyping by mass spectrometry. Men 50 years or older and women 60 or older were included for analysis. Acute, traumatic, and revision cases were excluded.

RESULTS

Of 185 patients who underwent CTR with tenosynovial biopsy, 54 (29%) demonstrated positive Congo red stain, confirmed by the external laboratory. A subtype analysis revealed wild-type transthyretin (TTR) in 44 patients (80%), mixed wild-type TTR with κ light chains in 1 patient, and hereditary TTR in 1 patient. Patients with positive specimens were significantly older than those who tested negative (77 vs 68 years, respectively), and positivity increased by decade for both sexes. Male sex, atrial fibrillation, and spinal stenosis were significantly more prevalent among positive cases. There were no complications from the biopsies.

CONCLUSIONS

We confirmed evidence of amyloidosis in the tenosynovium of 29% of men 50 years or older and women 60 or older who underwent CTR. The majority demonstrated wild-type TTR. As these patients are at risk of developing cardiomyopathy, there is an opportunity for early detection, monitoring, and interventions known to improve outcomes. Considering the low cost of Congo red staining and the potential value of subtyping with regard to treatment of cardiomyopathy, our findings support routine tenosynovial biopsy during CTR in patients who meet the age criteria.

TYPE OF STUDY/LEVEL OF EVIDENCE

Differential diagnosis or symptom prevalence study II.

Revision of Carpal Tunnel Surgery

Carpal tunnel release is one of the most commonly performed upper extremity procedures. The majority of patients experience significant improvement or resolution of their symptoms. However, a small but important subset of patients will experience the failure of their initial surgery. These patients can be grouped into persistent, recurrent, and new symptom categories. The approach to these patients starts with a thorough clinical examination and is supplemented with electrodiagnostic studies. The step-wise surgical management of revision carpal tunnel surgery consists of the proximal exploration of the median nerve, Guyon’s release with neurolysis, the rerelease of the transverse retinaculum, evaluation of the nerve injury, treatment of secondary sites of compression, and potential ancillary procedures. The approach and management of failed carpal tunnel release are reviewed in this article.