Younger patients, lower BMI, complete meniscus root healing, lower HKA degree and shorter preoperative symptom duration were the independent risk factors correlated with the good correction of MME in patients with repaired MMPRTs

PURPOSE

To evaluate the clinical and radiological outcomes of arthroscopically assisted tendon graft anatomic reinforced reconstruction of the medial meniscus posterior root tears (MMPRTs) and identify relevant factors affecting the correction of medial meniscal extrusion (MME).

METHODS

Fifty-three MMPRTs patients who underwent arthroscopically assisted tendon graft reconstruction of the meniscal root between 2018 and 2020 were evaluated retrospectively. the patients were divided into 2 groups according to the correction of MME (maintained MME group: 32 cases vs. increased MME group: 21 cases). The clinical and radiological outcomes of arthroscopically assisted tendon graft reconstruction of the meniscal root, including postoperative correction of MME and functional recovery of the knee were assessed in this study, and potential independent risk factors that could influence the correction of MME were also evaluated.

RESULTS

The functional recovery of the knee was significantly improved at the end of follow-up (P < 0.001; respectively), furthermore, a comparison of the final functional outcomes between the groups showed that the mean Lysholm score and IKDC score of the maintained MME group were significantly improved than those of increased MME group. 60.4% had good correction of MME, and patients with complete healing had better extrusion correction than those with partial healing and non-healing. Binary logistic regression models analysis indicated that the age (OR = 1.053, P = 0.048), BMI (OR = 1.376, P = 0.004), meniscus root healing status (OR = 7.701, P = 0.005), HKA degree (OR = 1.891, P = 0.011) and preoperative symptom duration (OR = 1.055, P = 0.013) were the independent risk factors correlated with correction of MME. Additionally, the ROC curve demonstrated the cut-off values of the Age, BMI, HKA degree and preoperative symptom duration were 46.0 years, 22.5 kg/m2, 3.2° and 9.5 months, respectively, CONCLUSIONS: The arthroscopically assisted tendon graft anatomic reinforced reconstruction of the meniscal root showed clinical improvement and prevented the progression of postoperative MME. Additionally, younger patients, lower BMI, complete meniscus root healing, lower HKA degree and shorter preoperative symptom duration were the independent risk factors correlated with the good correction of MME in patients with repaired MMPRTs.

LEVEL OF EVIDENCE

Level IV.

Clinical Assessment of Existence of Palmaris Longus Muscle among South Indian Population

Background: Palmaris longus tendon is often used as a donor tendon by surgeons in tendon grafts. It is one of the flexor muscles of the forearm and documented well for its variations in both morphology and number of tendons. Prevalence of absence of this muscle varies among the individuals of same population and individuals of various ethnic groups. The aim of this study was to assess the existence of Palmaris longus muscle within a group of students and its association with side of the limb and gender of the individual. Methods: Three hundred medical students of 150 males and 150 females with age group of 18-21 years were clinically assessed. The standard Schaffer's test was used for the assessment of PL tendon. If the tendon was not found in this test, the confirmation was done by other four tests. Results: Results of this study shows that an overall absence of palmaris longus muscle in both sexes was found to be 32%, out of which 21% absence was found in males and 43% absence found in females. Among the males, the unilateral agenesis was seen in 16% and bilateral agenesis in 4% and in females the unilateral agenesis was seen in 29% and bilateral agenesis seen in 14%. Conclusions: To conclude; in the present study, prevalence of Palmaris longus muscle agenesis was found to be more in female subjects on their left side. Surgeons who plan for tendon reconstructive procedures should know variations of Palmaris longus muscle and its clinical assessment.

Morphological variability of the palmaris longus muscle in human fetuses

Purpose

The palmaris longus (PL) muscle is characterized by high-morphological variability. It is clinically important as it is routinely harvested for the reconstruction of other tendons. The study characterizes the morphology of the PL in human fetuses and creates a new classification based on its variations that would relate to the spectrum of morphological variability in adults.

Methods

Eighty spontaneously aborted human foetuses (44 male, 36 female, 160 upper limbs), aged 18–38 weeks of gestation, were examined.

Results

The palmaris longus muscle was present in 62.5% of fetuses. The absence was bilateral in 26.25%, and unilateral in 22.5%. Nine types of palmaris longus muscles were identified based on the morphology of its insertion (Types I–IX). All types originated on the medial epicondyle of the humerus. The most common type was Type I, which was characterized by insertion to the palmar aponeurosis (52%). The rarest types were Type VII and Type IX (1% each). Type VII was characterized by partial doubling of the muscle belly, which then turned into two separate tendons that inserted together into the palmar aponeurosis. Type IX was characterized by fusion with the flexor carpi ulnaris muscle.

Conclusion

Our findings concerning morphological variability of the PL in fetuses present a new perspective on the understanding nature of the morphological variation of the PL muscle in adults.

List of evidence

Basic Science Study.

Anatomical variations of the palmaris longus muscle including its relation to the median nerve - a proposal for a new classification

BACKGROUND

The palmaris longus (PL) muscle is characterised by high morphological diversity, and its tendon crosses the median nerve (MN) at different levels. Due to the fact that the palmaris longus tendon is routinely harvested for reconstruction of other tendons, knowledge of its morphological variations is clinically important. Therefore, the purpose of the study was to suggest a new morphological classification of the PL muscle and characterise the relationship of its tendon to the median nerve.

METHODS

Standard dissection was performed on 80 randomised and isolated upper limbs (40 left and 40 right) fixed in a 10% formalin solution. Measurements of muscle belly and tendon were obtained. The course and location of tendon insertion, as well as its relationship to the median nerve, were noted.

RESULTS

The palmaris longus muscle was present in 92.5% of specimens. Three types of palmaris longus muscle were identified based on the morphology of its insertion (types I-III) and these were further subdivided into three subgroups (A-C) according to the ratio of the length of the muscle belly and its tendon. The most frequent was type I (78.8%), where the tendon attached to the palmar aponeurosis, and subtype B, where the tendon-to-belly ratio was 1-1.5 (41.1%). The mean distance from the interstyloid line to the crossing between the median nerve and the palmaris longus tendon was 31.6 mm. In addition, two types of palmaris longus were described.

CONCLUSION

The presented classification of palmaris longus muscle types allows a better characterization of its diversity and may be useful in planning tendon grafting.

A Case of Reverse Palmaris Longus Muscle- An Additional Muscle in the Anterior Compartment of the Forearm

It is uncommon to have additional muscles in the upper limb. Some of them may restrict the movements or compress the nerves and vessels, while others may go unnoticed. During the routine dissection for undergraduate medical students, we observed an additional muscle in the anterior compartment of the forearm in about 60-year-old male cadaver. The muscle had a prominent belly and a long tendon. Distally, it was attached to the flexor retinaculum by a short and thick tendon. Proximally, long tendon of the muscle passed between the flexor carpi ulnaris and palmaris longus and was attached to the common aponeurosis shared by the extensor carpi ulnaris and flexor digitorum profundus muscles. The additional muscle belly was supplied by a branch from the anterior interosseous nerve. The ulnar nerve and artery was passing deep to the fleshy belly of the muscle. The muscle reported here might compress the ulnar nerve and artery and may produce neurovascular symptoms. On the other hand, the tendon and fleshy belly of the muscle could be useful in muscle/tendon grafts. The observations made by us in the present case will supplement our knowledge of variations of the muscles in this region which could be useful for surgeons during the forearm and hand surgeries.

A Bitendinous Palmaris Longus: Aberrant Insertions and Its Clinical Impact - A Case Report

Palmaris longus, phylogenetically a retrogressive muscle, exhibits significant anatomical variations compared to other muscles of the upper extremity. It is of great surgical importance because, it is the first option tendon for graft procedures in various cosmetic, plastic and reconstructive surgeries. It has also been widely used in various tendon transfer procedures in treating facial paralysis, ptosis correction, lip augmentation and digital pulley reconstruction. We report a rare variant pattern of Palmaris longus with duplicated tendons and with multiple insertions to thenar and hypothenar muscles, fasciae and the flexor retinaculum along with its normal continuation as palmar aponeurosis. Variations in its insertions not only contribute, but also augment the various pathological processes such as Dupuytren's contracture, Carpal tunnel and Guyon's syndromes. So it is of utmost importance for surgeons, physicians and radiologists, to be aware of these variations, well in advance.