Re: 회전근개 중 가장 큰 근육 subscapularis tendon tear. 2020 .

[문형철]

견갑하근 파열 분류

Front Surg

. 2023 Mar 15;10:916694. doi: 10.3389/fsurg.2023.916694

Subscapularis tendon tear classification and diagnosis: A systemic review and meta-analysis

Hossein Saremi 1,*,†, Mohamadali seifrabiei 2,✉

• Author information
• Article notes
• Copyright and License information

PMCID: PMC10050355  PMID: 37009599

Abstract

Background

In the current study, we performed a systematic review and meta-analysis regarding the comparison of accuracy, sensitivity, and specificity of the techniques in diagnosing SSC tendon tears. Also, we performed a systematic review of the classification of SSC tendon tears.

Methods

English language, peer-reviewed journal publications from the first date available to March 2022 were extracted by searching PubMed and Web of Science databases. A forest plot was used to graphically show the results of pooled sensitivity, specificity, and accuracy of different diagnostic modalities.

Results

There were six studies on using MRI to diagnose subscapularis tendon tears, five studies on MRI, four studies on clinical examination, one on ultrasonography, and one on CT arthrography. Pooled sensitivity values for MRI, MRA, clinical examination, ultrasonography, and CT arthrography were 0.71 (CI: 0.54; 0.87), 0.83 (0.77; 0.88), 0.49 (0.31; 0.67), 0.39 (0.29; 0.51), and 0.90 (0.72–0.97), respectively. The pooled specificity values for MRI, MRA, clinical examination, ultrasonography, and CT arthrography were 0.93 (CI: 0.89; 0.96), 0.86 (0.75; 0.93), 0.89 (0.73; 0.96), 0.93 (0.88; 0.96), and 0.90 (0.69; 0.98), respectively. The pooled diagnostic accuracy values for MRI, MRA, clinical examination, ultrasonography, and CT arthrography were 0.84 (CI: 0.80; 0.88), 0.85 (0.77; 0.90), 0.76 (0.66; 0.84), 0.76 (0.70; 0.81), and 0.90 (0.78; 0.96), respectively.

Conclusion

According to our systematic review and meta-analysis, MR arthrography was the most accurate in diagnosing subscapularis tears. MR arthrography was the most sensitive, and MRI and ultrasonography were the most specific in detecting subscapularis tears.

배경

본 연구에서는 SSC 건 파열 진단 기법의 정확도, 민감도 및 특이도 비교에 관한 체계적 문헌고찰 및 메타분석을 수행하였다. 또한 SSC 건 파열의 분류에 관한 체계적 문헌고찰을 수행하였다.

방법

PubMed 및 Web of Science 데이터베이스를 검색하여 2022년 3월까지의 영어권 동료 심사 학술지 논문을 추출하였다. 포리스트 플롯을 사용하여 다양한 진단 기법의 통합 민감도, 특이도 및 정확도 결과를 그래픽으로 표시하였다.

결과

견갑하근 건 파열 진단에 MRI를 사용한 연구는 6건, MRI 연구는 5건, 임상 검진 연구는 4건, 초음파 연구는 1건, CT 관절조영술 연구는 1건이었다. 통합 감도 값은 MRI, MRA, 임상 검사, 초음파 검사, CT 관절조영술 순으로 각각 0.71(신뢰구간: 0.54; 0.87), 0.83(0.77; 0.88), 0.49(0.31; 0.67) , 0.39(0.29; 0.51), 0.90(0.72–0.97)이었다. MRI, MRA, 임상 검사, 초음파 검사, CT 관절조영술의 통합 특이도 값은 각각 0.93 (신뢰구간: 0.89; 0.96), 0.86 (0.75; 0.93), 0.89 (0.73; 0.96), 0.93 (0.88; 0.96), 0.90 (0.69; 0.98)이었다. MRI, MRA, 임상 검사, 초음파 검사 및 CT 관절 조영술의 통합 진단 정확도 값은 각각 0.84 (신뢰구간: 0.80; 0.88), 0.85 (0.77; 0.90), 0.76(0.66; 0.84), 0.76(0.70; 0.81), 0.90(0.78; 0.96)이었다.

결론

본 체계적 문헌고찰 및 메타분석에 따르면,

MR 관절조영술이 견갑하근 파열 진단에서 가장 정확했다.

MR 관절조영술은 가장 민감도가 높았고,

MRI와 초음파검사는 견갑하근 파열 감별에서 가장 특이도가 높았다.

Keywords: subscapularis tendon tear, MRI, MR arthrography, ultrasonography, clinical examination, CT arthrography

Background

The rotator cuff muscle group is formed by the subscapularis (SSC) muscle, supraspinatus muscle, infraspinatus muscle, and teres minor muscle at the posterior scapular region. The SSC muscle originates from the subscapularis fossa of the scapula, inserts into the lesser tubercle of the humerus, and is innervated by the superior and inferior subscapular nerves. The SSC muscle is the largest component of the aforementioned rotator cuff; it is responsible for the elevation and internal rotation of the shoulder and has a crucial role in stabilizing the glenohumeral joint (1). As the subscapularis tendon tear is a preval‎ent painful condition followed by a significant loss of function, timely diagnosis and management of this condition are of crucial importance (2).

배경

회전근개 근육군은

견갑골 후방 부위의 견갑하근(SSC), 상근, 하근, 소원근으로 구성됩니다.

SSC 근육은

갑골의 견갑하와에서 기시하여 상완골의 소결절에 삽입되며,

상하 견갑하 신경에 의해 신경 분포를 받습니다.

SSC 근육은 앞서 언급한 회전근개 중 가장 큰 구성 요소로,

어깨의 상승 및 내회전을 담당하며 견관절 안정화에 중요한 역할을 합니다(1) .

견갑하근 건 파열은

기능 저하를 동반한 흔한 통증 질환이므로,

이 질환의 시기적절한 진단과 관리가 매우 중요하다(2).

Until now, several classifications have been proposed by Fox et al., Lyons, Lafosse et al., and Touissant et al. (3–6). However, there is no consensus regarding the classification of this condition, which may hinder clinical eval‎uation, diagnosis, and management.

The most sensitive and specific clinical examinations to assess an SCC tendon tear are the lift-off test, the belly-press test, and the bear-hug test. Increased external rotation compared to normal shoulder rotation and weakness in internal rotation also help in the diagnosis (7). Although these tests are essential for the diagnosis of SSC tendon tears, various imaging modalities such as magnetic resonance imaging (MRI), computed tomography (CT) scanning, magnetic resonance arthrography (MRA), and ultrasonography (US) may also be indicated (8). Since the SCC plays a crucial role in shoulder function, eval‎uating diagnostic modalities is of great significance. Misdiagnosed SSC tendon tears may result in unbalanced force, persistent shoulder pain, and weakness even after cuff repair (9). The gold standard diagnostic test for SSC tendon tears is arthroscopy, which helps the physician precisely eval‎uate the humeral and glenoid aspects of the joint space (10). As arthroscopy is an invasive, technically demanding, and expensive technique, using the aforementioned clinical assessments and imaging modalities can replace the necessity of performing an arthroscopy to diagnose SCC tendon tears. While several studies have provided evidence-based guidelines for the examination, diagnosis, and management of SSC tendon tears, no previous systematic review and meta-analysis studies have eval‎uated the diagnostic accuracy of MRI, MRA, CT scanning, US, and clinical assessments in the diagnosis of SSC tendon tears. Also, as mentioned earlier in the manuscript, a consensus regarding the classification of SSC tendon tears is still lacking.

In the current study, we performed a systematic review and meta-analysis regarding the comparison of accuracy, sensitivity, and specificity of these techniques in diagnosing SSC tendon tears. Also, we performed a systematic review of the classification of SSC tendon tears.

지금까지 Fox 등, Lyons, Lafosse 등, Touissant 등이 여러 분류법을 제안해왔다(3–6).

그러나 이 질환의 분류에 대한 합의가 없어 임상적 평가, 진단 및 관리에 어려움을 초래할 수 있다.

견갑하근 건 파열을 평가하는 가장 민감하고 특이적인 임상 검사는

리프트오프 검사, 배리프레스 검사, 베어허그 검사이다.

정상 어깨 회전에 비해

증가된 외회전과 내회전 약화도 진단에 도움이 된다(7).

이러한 검사들은 SSC 건 파열 진단에 필수적이지만,

자기공명영상(MRI), 컴퓨터단층촬영(CT), 자기공명관조영술(MRA), 초음파검사(US) 등

다양한 영상 검사도 필요할 수 있다(8).

SSC는 어깨 기능에 중요한 역할을 하므로

진단적 검사의 평가가 매우 중요하다.

SSC 힘줄 파열을 오진할 경우,

회전근개 수복술 후에도 힘의 불균형, 지속적인 어깨 통증 및 근력 약화가 발생할 수 있다 (9).

SSC 힘줄 파열의 골드 스탠다드 진단 검사는

관절경 검사이며,

이는 의사가 관절 공간의 상완골 및 관절와 측면을 정확하게 평가하는 데 도움이 됩니다(10).

관절경 검사는 침습적이고 기술적으로 까다로우며 비용이 많이 드는 기법이므로,

앞서 언급한 임상 평가 및 영상 기법을 활용하면

SSC 힘줄 파열 진단을 위해 관절경 검사를 수행할 필요성을 대체할 수 있습니다.

여러 연구에서 SSC 건 파열의 검사, 진단 및 관리에 대한 근거 기반 지침을 제시했지만,

MRI, MRA, CT 촬영, 초음파 및 임상 평가가 SSC 건 파열 진단에서 보여주는

진단 정확도를 평가한 체계적 문헌고찰 및 메타분석 연구는 이전에 없었습니다.

또한 본 논문의 앞부분에서 언급한 바와 같이,

SSC 건 파열의 분류에 관한 합의는 여전히 부족합니다.

본 연구에서는 견갑하근 건 파열 진단에 있어

이들 기법의 정확도, 민감도, 특이도 비교에 관한 체계적 문헌고찰 및 메타분석을 수행하였다.

또한 견갑하근 건 파열 분류법에 대한 체계적 문헌고찰을 실시하였다.

Methods

We conducted a systematic review of the pieces of evidence for the diagnosis of subscapular tears with different diagnostic tools and studies on classification methods for subscapular tears. English language, peer-reviewed journal publications from the first date available to March 2022 were extracted by searching PubMed and Web of Science databases. The combination of the following search terms was used: subscapularis tear, diagnosis, and classification. After removing duplicate studies, the retrieved records were screened for title and abstract. The full text of eligible studies, selected from the previous step, was screened and reviewed. The data of interest were the sensitivity, specificity, and accuracy of different diagnostic tools in subscapularis tendon tears.

The eligible studies were observational studies (cross-sectional and cohort studies) on the diagnostic accuracy of imaging modalities and clinical assessments in subscapularis tendon tears. We excluded the studies that have one or more of the following criteria: (1) studies that were on rotator cuff tendons other than the subscapularis tendon (e.g., supraspinatus); (2) systematic reviews, meta-analysis studies, reviews, case reports, case series, and gray literature; (3) studies with no control group; (4) studies where the number of patients with subscapularis tendon tears was not specified; and (5) full text in any language other than English. For meta-analysis, we also excluded studies as reference tests other than arthroscopy (e.g., MRI or MR arthrography) because arthroscopy is the gold standard for diagnosing subscapularis tendon tears.

For data analysis, we used a meta package in R statistical software (version 4.1.1). The sensitivity, specificity, and accuracy of different diagnostic tests were calculated with a 95% confidence interval (CI). Sensitivity was considered as true-positive cases divided by total patients with a subscapularis tendon tear; specificity was considered as true-negative cases divided by total cases with an intact subscapularis tendon (confirmed by arthroscopy). Accuracy was considered as true-positive and true-negative cases divided by total subjects in the study. The random-effects model was used for calculating pooled sensitivity, specificity, and accuracy. In this study, subgroup analysis was used to report pooled sensitivity, specificity, and accuracy for different diagnostic tools. The forest plot was used to graphically represent the results of calculated pooled sensitivity, specificity, and accuracy for different subgroups. The I2 statistic was used to eval‎uate the heterogeneity in the included studies for each subgroup.

방법

우리는 다양한 진단 도구를 이용한 견갑하근 파열 진단에 대한 증거 자료와 견갑하근 파열 분류 방법에 관한 연구에 대한 체계적 문헌고찰을 수행하였다. PubMed 및 Web of Science 데이터베이스를 검색하여 2022년 3월까지의 영어권 동료검토 학술지 논문을 추출하였다. 다음 검색어 조합을 사용하였다: subscapularis tear, diagnosis, classification. 중복 연구를 제거한 후 검색된 기록을 제목 및 초록 기준으로 선별하였다. 이전 단계에서 선정된 적격 연구의 전문을 선별 및 검토하였다. 관심 데이터는 견갑하근 건 파열에서 다양한 진단 도구의 민감도, 특이도 및 정확도였다.

적격 연구는 견갑하근 건 파열에서 영상 검사법 및 임상 평가의 진단 정확도를 다룬 관찰 연구(횡단면 연구 및 코호트 연구)였다. 다음 기준 중 하나 이상을 충족하는 연구는 제외하였다: (1) 견갑하근 건 이외의 회전근개 건(예: 상근건)을 대상으로 한 연구; (2) 체계적 문헌고찰, 메타분석 연구, 리뷰, 사례보고, 사례시리즈 및 회색문헌; (3) 대조군이 없는 연구; (4) 견갑하근 건 파열 환자 수가 명시되지 않은 연구; (5) 영어가 아닌 다른 언어로 작성된 전문. 메타분석에서는 견갑하근 건 파열 진단에 관절경이 금기준이므로, 관절경 이외의 참조 검사(예: MRI 또는 MR 관절조영술)를 사용한 연구도 제외하였다.

데이터 분석에는 R 통계 소프트웨어(버전 4.1.1)의 meta 패키지를 사용하였다. 다양한 진단 검사의 민감도, 특이도 및 정확도는 95% 신뢰구간(CI)으로 계산하였다. 민감도는 진양성 사례를 견갑하근 건 파열 환자 총수로 나눈 값으로, 특이도는 진음성 사례를 견갑하근 건이 온전한 사례(관절경으로 확인) 총수로 나눈 값으로 정의하였다. 정확도는 진양성 및 진음성 사례를 연구 대상자 총수로 나눈 값으로 정의하였다. 통합 민감도, 특이도 및 정확도 계산에는 무작위 효과 모델을 사용하였다. 본 연구에서는 하위군 분석을 통해 다양한 진단 도구에 대한 통합 민감도, 특이도 및 정확도를 보고하였다. 포리스트 플롯을 사용하여 다양한 하위군에 대한 계산된 통합 민감도, 특이도 및 정확도 결과를 그래픽으로 표현하였다. 각 하위군에 포함된 연구들의 이질성을 평가하기 위해 I2 통계를 사용하였다.

Results

The flow diagram of selected studies is shown in Figure 1. After reming duplicate records, 305 studies retrieved from online databases were screened for title andabstract. Thirty-two studies accomplished the inclusion criteria for full-text review. Six studies were excluded, leading to a final inclusion of 26 studies. The characteristics of the selected studies are presented in Table 1. Among them, seven studies were on the classification of the subscapularis tendon tear and 19 studies were on the diagnosis of subscapularis tendon tear. One study was excluded from meta-analysis because the reference test was MRI and not arthroscopy. Eighteen studies were included in our meta-analysis, and of 2,593 total subjects, 892 had subscapularis tendon tears.

결과

선정된 연구의 흐름도는 그림 1에 제시되어 있다. 중복 기록을 제거한 후 온라인 데이터베이스에서 검색된 305편의 연구를 제목 및 초록 기준으로 선별하였다. 32편의 연구가 전문 검토를 위한 포함 기준을 충족하였다. 6편의 연구가 제외되어 최종적으로 26편의 연구가 포함되었다. 선정된 연구의 특성은 표 1에 제시되어 있다. 이 중 7건은 견갑하근 건 파열의 분류에 관한 연구였고, 19건은 견갑하근 건 파열의 진단에 관한 연구였다. 기준 검사가 관절경이 아닌 MRI였던 1건의 연구는 메타분석에서 제외되었다. 총 18건의 연구가 메타분석에 포함되었으며, 총 2,593명의 대상자 중 892명이 견갑하근 건 파열을 가지고 있었다.

Figure 1.

Open in a new tab

Flow diagram of the selection process.

Table 1.

Characteristics of included studies.

AuthorYearStudy designDiagnosis modalityMean ageNumber of patientsSTTTPTNFPFNReference test

MR arthrography
Khila (11)	2020	Retrospective	MRA	63.1	180	31	27	146	3	4	Arthroscopy
Khilb (11)	2020	Retrospective	MRA	62.8	241	92	68	121	28	24	Arthroscopy
Jungc (12)	2017	Retrospective	MRA	57	84	30	24	39	15	6	Arthroscopy
Jungd (12)	2017	Retrospective	MRA	56	83	40	30	38	5	10	Arthroscopy
Oh (13)	2009	Prospective	MRA	55	36	21	17	12	3	4	Arthroscopy
Chooe (14)	2012	Retrospective	MRA	57.9	49	21	19	20	8	2	Arthroscopy
Choof (14)	2012	Retrospective	MRA	57.9	49	21	19	19	9	2	Arthroscopy
Lee (15)	2014	Retrospective	MRA	Median: 54	112	67	60	43	2	7	Arthroscopy
MRI
Saremi (16)	2019	Retrospective	MRI	57.67	85	41	16	44	0	25	Arthroscopy
Atinga (17)	2021	Retrospective	MRI	56	55	19	12	34	2	7	Arthroscopy
Lee (18)	2019	Retrospective	MRI	Median: 57	112	67	51	43	2	16	Arthroscopy
Gyftopoulos (19)	2013	Retrospective	MRI	48	244	25	20	199	20	5	Arthroscopy
Malavolta (20)	2016	Retrospective	MRI	NA	93	50	39	37	6	11	Arthroscopy
Matsushitag (21)	2022	Retrospective	MRI	NA	196	53	24	138	5	28	Arthroscopy
Matsushitah (21)	2022	Retrospective	MRI	NA	196	53	49	126	17	4	Arthroscopy
Clinical examination
Bartsch (22)	2010	Prospective	Clinical examination	58	50	15	6	23	6	9	Arthroscopy
Somerville (23)	2014	Prospective	Clinical examination	46	139	19	4	105	4	15	Arthroscopy with MRA
Lin (24)	2015	Prospective	Clinical examination	51	235	78	47	85	39	31	Arthroscopy
Takeda (25)	2016	Prospective	Clinical examination	65	130	46	30	69	4	16	Arthroscopy
Yoon (26)	2013	Retrospective	Clinical examination	57	312	133	16	179	0	117	MRI
Ultrasonography
Narasimhan (27)	2016	Retrospective	Ultrasonography	NA	236	74	29	151	11	45	Arthroscopy
CT arthrography
Asmar (28)	2020	Prospective	CT arthrography	54.1	50	29	26	19	2	3	Arthroscopy

Open in a new tab

MRI, magnetic resonance imaging; MRA, magnetic resonance arthrography; STT, subscapularis tendon tear; TP, true positive; TN, true negative; FP, false positive; FN, false negative.

a 

Full-thickness tear.

b 

Partial thickness tear.

c 

Anterior approach.

d 

Posterior approach.

e 

Two dimensional.

f 

Three dimensional.

g 

cMRI.

h 

rMRI.

Accuracy of different types of methods in the diagnosis of subscapularis tendon tears

There were six studies on using MRI to diagnose subscapularis tendon tears, five studies on MRI, four studies on clinical examination, one on ultrasonography, and one on CT arthrography. As shown in Figure 2, the pooled sensitivity values for MRI, MRA, clinical examination, ultrasonography, and CT arthrography were 0.71 (CI: 0.54; 0.87), 0.83 (0.77; 0.88), 0.49 (0.31; 0.67), 0.39 (0.29; 0.51), and 0.90 (0.72–0.97), respectively. The I2 statistic for each subgroup is shown in Figure 2. The pooled specificity values for MRI, MRA, clinical examination, ultrasonography, and CT arthrography were 0.93 (CI: 0.89; 0.96), 0.86 (0.75; 0.93), 0.89 (0.73; 0.96), 0.93 (0.88; 0.96), and 0.90 (0.69; 0.98), respectively. The I2 statistic for each subgroup is shown in Figure 3. The pooled diagnostic accuracy values for MRI, MRA, clinical examination, and CT arthrography were 0.84 (CI: 0.80; 0.88), 0.85 (0.77; 0.90), 0.76 (0.66; 0.84), 0.76 (0.70; 0.81), and 0.90 (0.78; 0.96) respectively. The I2 statistic for each subgroup is shown in Figure 4.

Figure 2.

Open in a new tab

Forest plot of sensitivity of different diagnostic modalities.

Figure 3.

Open in a new tab

Forest plot of specificity of different diagnostic modalities.

Figure 4.

Open in a new tab

Forest plot of diagnostic accuracy of different diagnostic modalities.

Classification of subscapularis tendon tears

Seven studies were found on the classification of subscapularis tendon tears (3–6, 29, 30). The different classification types are listed in Table 2.

Table 2.

Different classification systems.

TypeDescription

Lafosse’s classification
I	Partial lesion of superior one-third
II	Complete lesion of superior one-third
III	Complete lesion of superior two-thirds
IV	Complete lesion with centered head and fatty degeneration < stage3
V	Complete lesion with eccentric head and fatty degeneration > stage3
Yoo and Rhee’s subscapularis tendon tear classification
I	Fraying or longitudinal split of the subscapularis leading-edge tendon
IIA	<50% subscapularis tendon detachment in the first facet (concealed lesion included)
IIB	>50% detachment in the first facet without complete disruption of the lateral band (concealed lesion included)
III	Entire first facet with complete disruption of the lateral band (full-thickness tear of upper one-third of the subscapularis superior–inferior length)
IV	Up to the second facet tear: the first and second facets are exposed with much more medial retraction of the tendon, which is approximately a two-thirds tear of the entire subscapularis superior–inferior length (the entire tendinous portion)
V	Complete subscapularis tendon tear involving the muscular portion
Fox and Romeo’s classification
I	Partial-thickness tear
II	Complete tear of upper 25%
III	Complete tear of upper 50%
IV	Complete rupture
Martetschläger’s classification (for partial tears)
I	Split lesion
II	Tear smaller than 10 mm
III	Tear between 10 and 15 mm
IV	Tear larger than 15 mm
Lyons's classification
I	Partial thickness, partial length
II	Full thickness, partial length
III	Full thickness, full length without retraction
IV	Full thickness, full length with retraction
Toussaint’s classification
I	Partial tendon tear with intact bicipital sling
II	Partial tendon tear with partial bicipital sling injury with intact SGHL
III	Complete tendon tear with complete bicipital sling injury, minimal tendon retraction
IV	Complete tendon tear with complete bicipital sling injury, with retraction
Dierckman’s classification
I	Distinct, isolated nodule found on the leading edge of the subscapularis tendon with minimal degeneration
II	Longitudinal split tear of the upper ½ of the tendon without significant degeneration
III	Longitudinal tear of the upper ½ of the tendon with significant degeneration and fibrillation

Open in a new tab

Discussion

To our knowledge, this is the first systematic review and meta-analysis comparing the accuracy of different methods in diagnosing subscapularis tears. Our systematic review and meta-analysis showed that MR arthrography and CT arthrography were the most accuracte in diagnosing subscapularis tears, with accuracy values of 85% and 90%, respectively. However, there was only one study on the diagnostic accuracy of CT arthrography, and one is not enough to conclude. MRA and CT arthrography were the most sensitive, with a sensitivity of 83% for MR arthrography and 90% for CT arthrography. Again, the results could not be reliable due to the low sample size in CT arthrography. MRI and ultrasonography were the most specific in detecting subscapularis tears, with a specificity of 93% for both of them. However, ultrasonography has much lower sensitivity, resulting in lower accuracy than MRI.

Clinical assessment and imaging studies are the two main methods for diagnosing subscapularis tendon tears (9). Generally, our meta-analysis showed that imaging studies are more accurate, sensitive, and specific than clinical assessment in the diagnosis of subscapularis tendon tears. However, clinical assessments could have high specificity in detecting such disorders. The patients may report weakness in internal rotation but is nonspecific of a subscapularis tendon tear. In our study, the clinical test used for the diagnosis of subscapularis tendon tear was the lift-off test; a previous meta-analysis of the lift-off test by Lädermann et al. showed that it has the highest accuracy among all clinical tests (31). However, clinical tests are subjective. The subscapularis tendon strength can be assessed by a dynamometer, which provides force comparison with the contralateral shoulder and objective values (9).

Ultrasonography is among other imaging techniques for the diagnosis of subscapularis tendon disorders . Although there are numerous studies on the accuracy of ultrasonography for diagnosing rotator cuff tendon tears particularly supraspinatus tendon tears, there are limited studies on the accuracy of ultrasonography in diagnosing subscapularis tendon tears (32). A meta-analysis conducted by Farooqi et al. on the diagnostic accuracy of ultrasonography for rotator cuff tears showed that ultrasonography has a more diagnostic accuracy for bicep tendon tears (93%) and supraspinatus tendon tears (83%) compared to subscapularis tendon tears (76%). However, ultrasonography is highly specific in detecting subscapularis tendon tears (93%) compared to other imaging modalities. Thus, a positive result could be considered for subsequent definitive diagnosis and management procedures such as arthroscopy, but a negative result needs more diagnostic tests to approve. Further studies on assessing the diagnostic accuracy of ultrasonography for subscapularis tendon tears are required to make more definitive conclusions.

MRI and MR arthrography are more reliable compared to ultrasonography or clinical assessment for the diagnosis of subscapularis tendon tears (33). A meta-analysis conducted by Malavolta et al. on the efficacy of MRI and MR arthrography in the diagnosis of subscapularis tendon tears showed that the pooled sensitivity and specificity of MRI and MR arthrography in the diagnosis of the subscapularis tendon tears were 68% and 90%, respectively. However, this study did not conduct a separate meta-analysis for MRI and MR arthrography (33). Our study is in line with this meta-analysis as the sensitivity of MRI and MR arthrography is lower than their specificity, which means that MRI and MR arthrography have lower false-positive cases than false-negative cases. Previous studies show that the diagnostic value of MRI is higher in a complete tear of the subscapularis tendon (Type 4 by the Lafosse classification) (16) and the tear of the other rotator cuff tendons (34). The relatively lower sensitivity of MRI and MR arthrography for subscapularis tendon tears than that for other rotator cuff tendons could be explained by its three-dimensional footprint topography of the humeral head, which is explained by Yoo et al. (30), or by some noninsertional types of subscapularis tears (35). $$$$The accuracy also increases with the higher expertise of the reviewer (36). On the other hand, the diagnostic accuracy of MRI and MR arthrography is not affected by the time elapsed from injury to perform the imaging study (16).

Considering the accuracy of each diagnostic tool is important to obtain good clinical and functional outcomes in the treatment of subscapularis tendon tears (37, 38), although treatment of elderly patients is often limited surgically due to the bad quality of the tissue. Hence, a shoulder replacement could be indicated (39).

Classifications of Lafosse (Figures 5A-E), Fox, Lyons, Martetschlager, and Toussaint are based on the insertion site lesions and according to anatomic data and arthroscopic lesion-related findings (3–6, 29). Yoo et al. described a classification based on a three-dimensional anatomic footprint (30). Dierckman’s classification was based on noninsertional tendinopathy of the subscapularis (40). None of the classifications included interstitial tears of the subscapularis tendon described by Saremi et al. (Figure 5F) (35).

Figure 5.

Open in a new tab

Arthroscopic view of the Lafosse classification of subscapularis tendon tears (A–D) (4), airbag sign, an arthroscopic finding of interstitial tears of the subscapularis tendon (35).

The main strengths of this study are as follows: (1) this is the first systematic review and meta-analysis comparing the accuracy of different methods in diagnosing subscapularis tears; (2) this study compared not only the different imaging modalities but also the accuracy of imaging modalities with clinical examinations; and (3) we conducted a meta-analysis of the sensitivity and specificity in addition to the accuracy of different diagnostic modalities.

The limitation of this study is that we did not compare the specific clinical tests, and we also did not compare complete and partial tears of the subscapularis tendon tear. However, adding another level of subgroups could have affected the possibility of conducting a meta-analysis.

Conclusion

According to our systematic review and meta-analysis, MR arthrography was the most accurate in diagnosing subscapularis tears, MR arthrography was the most sensitive, and MRI and ultrasonography were the most specific in detecting subscapularis tears. Further studies on assessing the diagnostic accuracy of ultrasonography and CT arthrography for subscapularis tendon tears are required to make more definitive conclusions.

Data availability statement

The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author.

Author contributions

HS: drafted the manuscript, performed the literature search and drafted figures, edited the manuscript and supervised the whole study. MS drafted the manuscript, helped in correct literature search, contributed in data analysis and edited manuscript.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher's note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be eval‎uated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

References

• 1.Aguirre K, Mudreac A, Anatomy KJ. Shoulder and upper limb, subscapularis muscle. [Updated 2021 Aug 7]. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available at: https://www.ncbi.nlm.nih.gov/books/NBK513344/ [PubMed]
• 2.Arai R, Sugaya H, Mochizuki T, Nimura A, Moriishi J, Akita K. Subscapularis tendon tear: an anatomic and clinical investigation. Arthroscopy. (2008) 24(9):997–1004. 10.1016/j.arthro.2008.04.076 [DOI] [PubMed] [Google Scholar]