Distal Musculotendinous T Junction Injuries of the Biceps Femoris: An MRI Case Review

Background:

Injury to the distal musculotendinous T junction (DMTJ) of the biceps femoris is a distinct clinical entity that behaves differently from other hamstring injuries due to its complex, multicomponent anatomy and dual innervation. Injury in this region demonstrates a particularly high rate of recurrence, even with prolonged rehabilitation times.

Purpose:

To describe the anatomy of the DMTJ of the biceps femoris and analyze the injury patterns seen on magnetic resonance imaging (MRI) to aid prognosis and rehabilitation and minimize the risk of recurrence.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

Acute injury to the DMTJ of the biceps femoris was identified in 106 MRI examinations from 55 patients at a single institution. Each injury was classified as involving the long head, the short head, or both components of the DMTJ, with each component individually graded. Injuries were classified as recurrent if there was a previous MRI demonstrating an acute injury to the DMTJ or if there was scarring present at the site of an acute injury.

Results:

Of the 106 acute injuries to the DMTJ of the biceps femoris, isolated injury to the long head component was the most common (51%), with both components involved in [round 42.5% to 43%] of cases. Isolated injury to the short head component accounted for 7% of cases. The recurrence rate for reinjury to the DMTJ was 54% in this series. The date of prior injury was known in 45 of 57 recurrent cases, with 34 of these reoccurring within 3 months (76%) and 40 reoccurring within 12 months (89%). The recurrent injury was of a higher grade than the prior injury in 22 of 44 instances (50%), the same grade in 16 instances (36%), and a lower grade in 6 instances (14%). Thus, 86% of recurrent injuries were of the same or higher grade than prior injury.

Conclusion:

These results suggest that high-risk muscle injuries, such as that to the DMTJ of the biceps femoris, should be evaluated using MRI to determine the structural components involved and to assess the extent and severity of injury.

'Serious thigh muscle strains': beware the intramuscular tendon which plays an important role in difficult hamstring and quadriceps muscle strains

Why do some hamstring and quadriceps strains take much longer to repair than others? Which injuries are more prone to recurrence? Intramuscular tendon injuries have received little attention as an element in 'muscle strain'. In thigh muscles, such as rectus femoris and biceps femoris, the attached tendon extends for a significant distance within the muscle belly. While the pathology of most muscle injures occurs at a musculotendinous junction, at first glance the athlete appears to report pain within a muscle belly. In addition to the musculotendinous injury being a site of pathology, the intramuscular tendon itself is occasionally injured. These injuries have a variety of appearances on MRIs. There is some evidence that these injuries require a prolonged rehabilitation time and may have higher recurrence rates. Therefore, it is important to recognise the tendon component of a thigh 'muscle strain'.

Pattern of Fascicular Involvement in Midportion Achilles Tendinopathy at Ultrasound

BACKGROUND

The Achilles tendon is composed of fascicles from the soleus and gastrocnemius muscles, which are identifiable as discrete components at anatomical dissection.

HYPOTHESIS

The pattern of fascicular involvement in Achilles tendinopathy may be characterized at ultrasound, and this characterization is reliable between different observers.

STUDY DESIGN

Cross-sectional diagnostic study.

LEVEL OF EVIDENCE

Level 3.

METHODS

One hundred cases of Achilles tendinopathy were retrospectively evaluated by 2 blinded musculoskeletal radiologists. Using a short-axis anatomical map, each case was categorized as involving the fascicular territories of the medial head of gastrocnemius, lateral head of gastrocnemius, soleus, or combinations of these, or as indeterminate.

RESULTS

Both radiologists agreed on the fascicular involvement pattern in 93 of 100 cases; 20 involved only medial gastrocnemius territories, 8 lateral gastrocnemius, 15 soleus, 3 medial and lateral gastrocnemius, 21 medial gastrocnemius and soleus, 9 soleus and lateral gastrocnemius, and 16 the entire tendon, and 1 case was classified as indeterminate. In 7 cases, the interpretations were discordant. The kappa value was calculated as 0.92 (95% CI, 0.86-0.98) in keeping with a high level of interobserver agreement.

CONCLUSION

As assessed at ultrasound, most cases of Achilles tendinopathy involve the medial head of gastrocnemius and/or soleus fascicles.

CLINICAL RELEVANCE

The provided observational data will increase understanding of patterns of Achilles tendinopathy.

A soft patellar tendon on ultrasound elastography is associated with pain and functional deficit in volleyball players

OBJECTIVES

To investigate the diagnostic performance of grey scale Ultrasound (US), power Doppler (PD) and US elastography for diagnosing painful patellar tendinopathy, and to establish their relationship with Victorian Institute of Sport Assessment-Patella (VISA-P) scores in a group of volleyball players with and without symptoms of patellar tendinopathy.

DESIGN

Cross-sectional study.

METHODS

Thirty-five volleyball players (70 patellar tendons) were recruited during a national university volleyball competition. Players were imaged with conventional US followed by elastography. The clinical findings of painful patellar tendons were used as the reference standard for diagnosing patellar tendinopathy. In addition, all participants completed the VISA-P questionnaires.

RESULTS

Of the 70 patellar tendons, 40 (57.1%) were clinically painful. The diagnostic accuracy of grey scale US, PD and elastography were 60%, 50%, 62.9%, respectively, with sensitivity/specificity of 72.5%/43.3%, 12.5%/100%, and 70%/53.3%, respectively. Combined US elastography and grey scale imaging achieved 82.5% sensitivity, 33.3% specificity and 61.4% accuracy while routine combination technique of PD and grey scale imaging revealed 72.5% sensitivity, 43.3% specificity and 60.0% accuracy. Tendons in players categorized as soft on elastography had statistically significantly greater AP thickness (p<0.001) and lower VISA-P scores (p=0.004) than those categorized as hard. There was no significant association between grey scale US abnormalities (hypoechogenicities and/or fusiform swelling) and VISA-P scores (p=0.098).

CONCLUSIONS

Soft tendon properties depicted by US elastography may be more related to patellar tendon symptoms compared to grey scale US abnormalities. The supplementation of US elastography to conventional US may enhance the sensitivity for diagnosing patellar tendinopathy in routine clinical practice.

Ultrasound-guided platelet-rich plasma injection for distal biceps tendinopathy

BACKGROUND

Distal biceps tendinopathy is an uncommon cause of elbow pain. The optimum treatment for cases refractory to conservative treatment is unclear. Platelet-rich plasma has been used successfully for other tendinopathies around the elbow.

METHODS

Six patients with clinical and radiological evidence of distal biceps tendinopathy underwent ultrasound-guided platelet-rich plasma (PRP) injection. Clinical examination findings, visual analogue score (VAS) for pain and Mayo Elbow Performance scores were recorded.

RESULTS

The Mayo Elbow Performance Score improved from 68.3 (range 65 to 85) (fair function) to 95 (range 85 to 100) (excellent function). The VAS at rest improved from a mean of 2.25 (range 2 to 5) pre-injection to 0. The VAS with movement improved from a mean of 7.25 (range 5 to 8) pre-injection to 1.3 (range 0 to 2). No complications were noted.

DISCUSSION

Ultrasound-guided PRP injection appears to be a safe and effective treatment for recalcitrant cases of distal biceps tendinopathy. Further investigation with a randomized controlled trial is needed to fully assess its efficacy.

ESX1-dependent fractalkine mediates chemotaxis and Mycobacterium tuberculosis infection in humans

Mycobacterium tuberculosis-induced cellular aggregation is essential for granuloma formation and may assist establishment and early spread of M. tuberculosis infection. The M. tuberculosis ESX1 mutant, which has a non-functional type VII secretion system, induced significantly less production of the host macrophage-derived chemokine fractalkine (CX3CL1). Upon infection of human macrophages ESX1-dependent fractalkine production mediated selective recruitment of CD11b+ monocytic cells and increased infection of neighbouring cells consistent with early local spread of infection. Fractalkine levels were raised in vivo at tuberculous disease sites in humans and were significantly associated with increased CD11b+ monocytic cellular recruitment and extent of granulomatous disease. These findings suggest a novel fractalkine-dependent ESX1-mediated mechanism in early tuberculous disease pathogenesis in humans. Modulation of M. tuberculosis-mediated fractalkine induction may represent a potential treatment option in the future, perhaps allowing us to switch off a key mechanism required by the pathogen to spread between cells.

Undetected multidrug-resistant tuberculosis amplified by first-line therapy in mixed infection

Infections with >1 Mycobacterium tuberculosis strain(s) are underrecognized. We show, in vitro and in vivo, how first-line treatment conferred a competitive growth advantage to amplify a multidrug-resistant M. tuberculosis strain in a patient with mixed infection. Diagnostic techniques that identify mixed tubercle bacilli populations are needed to curb the spread of multidrug resistance.

Undetected multidrug-resistant tuberculosis amplified by first-line therapy in mixed infection

Infections with >1 Mycobacterium tuberculosis strain(s) are underrecognized. We show, in vitro and in vivo, how first-line treatment conferred a competitive growth advantage to amplify a multidrug-resistant M. tuberculosis strain in a patient with mixed infection. Diagnostic techniques that identify mixed tubercle bacilli populations are needed to curb the spread of multidrug resistance.

Shoulder Structure and Function Following the Modified Latarjet Procedure: A Clinical and Radiological Review

BACKGROUND

To evaluate the clinical and radiological outcomes of the modified Latarjet procedure for traumatic, antero-inferior glenohumeral joint instability.

METHODS

Case series were used with a mean follow-up of 21.3 months for clinical and radiological review and 47.2 months for recurrent instability. Shoulder function was evaluated by clinical examination and validated shoulder scales: Western Ontario Shoulder Stability Index (WOSI), Melbourne Instability Shoulder Score (MISS) and l'Insalata Shoulder Questionnaire. Shoulder structure was evaluated by computed tomography.

RESULTS

Thirty-two cases were enrolled (mean age 27.0 years). One patient reported a redislocation during the follow-up period. Clinical examination revealed that the median external rotation (at 0° and 90° abduction) was reduced on the operative side by 7.5° (p < 0.01) and 10° (p < 0.001), respectively. Subjective shoulder function was good. Mean (SD) scores on the WOSI, MISS and l'Insalata scales were 78.0 (19.7), 75.8 (11.5) and 89.3 (9.9), respectively. No loss of subscapularis strength was identified (p > 0.05). Radiological evaluation revealed a mean (SD) pre-operative glenoid surface area loss of 169.5 (48.5) mm(2) reconstituted surgically by a bone block of 225.4 (73.8) mm(2). Subscapularis muscle bulk was reduced on the operative side, above the level of the muscle split (p < 0.05).

CONCLUSIONS

The Latarjet procedure reliably restores lost glenoid surface area, shoulder stability, strength and function. A small loss of external rotation is expected and related to altered subscapularis anatomy.

Return to competitive play after hamstring injuries involving disruption of the central tendon

BACKGROUND

The hamstring muscles are the most commonly injured muscle group in many different sports. Recovery time is often unpredictable and prolonged, and recurrent injury is common.

HYPOTHESIS

Hamstring injuries that disrupt the central tendon enclosed within the muscle belly require a longer recovery time than do injuries involving only muscle, epimysial fascia, or the musculotendinous junction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Injury records from professional sports teams were reviewed to determine the length of recovery from each hamstring injury that occurred over a 24-month period. The integrity of the central tendon on magnetic resonance imaging (MRI) was retrospectively reviewed for each case. The association between central tendon disruption on MRI and recovery time was determined.

RESULTS

There were 62 hamstring injuries included for analysis; 45 (72%) involved the biceps femoris, 11 (18%) involved the semimembranosus, and 6 (10%) involved the semitendinosus. Central tendon disruption was identified in 12 (45%) of the biceps femoris injuries and in none of the injuries to the other 2 muscles. Three of these injuries were treated surgically, with a median recovery time of 91 days. The median (interquartile range [IQR]) recovery times for those remaining biceps femoris injuries with and without central tendon disruption were 21 days (IQR, 9-28) and 72 days (IQR, 42-109), respectively (P < .01).

CONCLUSION

Disruption of the central tendon in injuries to the biceps femoris results in a significantly longer recovery time than injuries that do not disrupt the central tendon. This highlights the distinction between injury to the hamstring muscle and injury to the hamstring tendon, which is underappreciated as being a distinct entity when injury involves the enclosed central portion of the tendon.

The prevalence and clinical significance of sonographic tendon abnormalities in asymptomatic ballet dancers: a 24-month longitudinal study

INTRODUCTION

Sonographic abnormalities of the achilles and patellar tendons are common findings in athletes, and tendinopathy is a common cause of pain and disability in athletes. However, it is unclear whether the sonographic changes are pathological or adaptive, or if they predict future injury. We undertook a cohort study to determine what sonographic features of the achilles and patellar tendons are consistent with changes as a result of ballet training, and which may be predictive of future development of disabling tendon symptoms.

METHODS

The achilles and patellar tendons of 79 (35 male, 44 female) professional ballet dancers (members of the English Royal Ballet) were examined with ultrasound, measuring proximal and distal tendon diameters and assessing for the presence of hypoechoic change, intratendon defects, calcification and neovascularity. All subjects were followed for 24 months for the development of patellar tendon or achilles-related pain or injury severe enough to require time off from dancing.

RESULTS

Sonographic abnormalities were common among dancers, both male and female, and in both achilles and patellar tendons. Disabling tendon-related symptoms developed in 10 dancers and 14 tendons: 7 achilles (3 right, 4 left) and 7 patellar (2 right, 5 left). The presence of moderate or severe hypoechoic defects was weakly predictive for the development of future disabling tendon symptoms (p=0.0381); there was no correlation between any of the other sonographic abnormalities and the development of symptoms. There was no relationship between achilles or patellar tendons' diameter, either proximal or distal, with an increased likelihood of developing tendon-related disability.

CONCLUSION

The presence of sonographic abnormalities is common in ballet dancers, but only the presence of focal hypoechoic changes predicts the development of future tendon-related disability. This suggests that screening of asymptomatic individuals may be of use in identifying those who are at higher risk of developing tendon-related disability, which may in turn allow targeted modifications of training or other preventative regimens.

Radiofrequency denervation of the inguinal ligament for the treatment of 'Sportsman's Hernia': a pilot study

BACKGROUND

Chronic groin pain is a common and debilitating condition in highly active athletes. Symptoms are often ascribed to the so-called Sportsman's Hernia, and these patients frequently undergo prolonged and often painful remedial physiotherapy, or, if the condition is refractory, surgery to repair the posterior inguinal wall.

HYPOTHESIS

We hypothesised that radiofrequency denervation (RFD) of both the ilioinguinal nerve and inguinal ligament could be used to desensitise the groin region and enable the athlete to become pain-free.

STUDY DESIGN

A prospective randomised controlled trial of three groups of patients with chronic groin pain.

METHODS

Thirty-six patients with chronic groin pain of greater than 6 months duration, with no identifiable structural cause and which was refractory to conservative treatment, were randomised into two groups. Group 1 was treated with RFD (n=18), while group 2 was treated with local anaesthetic (Bupivicaine) and steroid (Trimacinolone) injection (n=18). A further 10 patients with previous failed surgery for the same condition were treated with RFD without randomisation. All patients then underwent a standardised physiotherapy regimen. The Visual Analogue Scale at rest (VASr) and with activity (VASa) was used to assess pain, and London Adductor and Abdominal Groin Score was used to assess function, at baseline and at 1 week, 3 months and 6 months post-treatment.

RESULTS

RFD treatment resulted in a significant improvement above baseline in all measures and at each time intervals up to 6 months, in both the randomised Group 1 and in the postsurgery group (p values ranging from <0.001 to 0.001). Injection of local anaesthetic and steroid resulted in a significant improvement above baseline in all measures, but only at 1 week (p values ranging from 0.001 to 0.021), and not at any of the later intervals. Improvements in all measures was significantly greater in Group 1 than in Group 2 at all follow-up intervals (p values ranging from <0.001 to 0.003). No persistent adverse events were recorded.

CONCLUSIONS

The use of RFD in the treatment of refractory Sportsman's Hernia is safe and efficacious at least in the short term, and is superior to anaesthetic/steroid injection. The results suggest that symptoms are related to tendon inflammation and ilioinguinal nerve compression, and can be abolished with pharmacological or radiofrequency treatment, without the need for surgery.

CLINICAL RELEVANCE

This novel technique could help athletes suffering from chronic groin pain return to play more quickly, both facilitating and allowing deferral of remedial physiotherapy treatments, and potentially avoiding the need for surgery.