Interobserver and intraobserver reliability of different methods of examination for presence of palmaris longus and examination of fifth superficial flexor function

Abstract

The palmaris longus is harvested as a tendon graft in various surgical procedures. Several tests are used to assess the presence of palmaris longus tendon. In the present study, we attempted to assess the interobserver and intraobserver reliability of five of the most famous methods and also the examination of fifth superficial flexor function. Two observers, who had been trained on the tests and had practiced them, examined 105 volunteers on two separate occasions and in 1-month interval the results were recorded. The reliability of each method was assessed with Kappa measurement. Kappa ranged from 0.541 (moderate reliability) to 0.813 (almost complete agreement) for palmaris. The highest interobserver and intraobserver reliability and also the best agreement with other tests were of Schaeffer. The lowest kappa was for Thompson and the others have good to excellent reliability. Kappa for interobserver and intraobserver reliability for the fifth flexor were 0.415 and 0.500 (moderate reliability), respectively. The tests that were assessed have good reliability except for Thompson that has a moderate one. It seems that the standard test (Schaeffer) is the best method for the assessment of the absence or presence of palmaris longus. The method used for the evaluation of fifth superficial flexor variations assessment has a moderate interobserver and intraobserver reliability.

Clinical tests for assessing the presence and quality of the palmaris longus tendon: diagnostic accuracy of examination compared with ultrasound

“…Mishra’s two tests examine for different actions of the PL, with the first test isolating the PL as a weak wrist flexor and the second testing the PL as a stabilizer of the superficial structures in the palm in preparation for abduction of the thumb (Fahrer, 1973; Fahrer and Tubiana, 1976; Mishra, 2001; Sebastin and Lim, 2006). Based on this, one may expect Schaeffer’s standard test and Thompson’s test to have similar diagnostic accuracy, but in the present study and others (Kigera and Mukwaya, 2012; Sadeghifar et al., 2018), Schaeffer’s standard test is preferred to Thompson’s. This difference has been attributed to inadequate abduction of the thumb in Thompson’s test, as patients often initially place their thumb over the dorsum of the middle or index finger rather than over the ring or small finger (Sebastin and Lim, 2006).…”

“…Previous studies have compared various clinical tests to detect the PL tendon (Kigera and Mukwaya, 2012; Kyung et al., 2012; Machhindra et al., 2015; Ndou et al., 2010; Sadeghifar et al., 2018), and three of these five also found Schaeffer’s standard test to be the most ‘accurate’ in detecting the PL tendon (Kigera and Mukwaya, 2012; Kyung et al., 2012; Sadeghifar et al., 2018). However, none of these studies verified the accuracy of the examination manoeuvres against surgical dissection or advanced imaging.…”

“…While the examiners in the present study are attending orthopaedic surgeons with over 60 years of combined experience, examiners in previous studies included medical school or physician assistant students (Kigera and Mukwaya, 2012; Sadeghifar et al., 2018) and first year orthopaedic residents (Machhindra et al., 2015). The most common difficulty reported in the examination for the presence of the PL is the misinterpretation of the flexor carpi radialis as the PL, and novice examiners are more susceptible to this mistake than experienced examiners (Sadeghifar et al., 2018; Sebastin and Lim, 2006). The accuracy of clinical tests may be influenced by patient factors, such as the ability to cooperate, individual anatomy, and body habitus.…”

“…A variety of clinical manoeuvres have been described to assess PL tendon presence, including Schaeffer’s standard test (Schaeffer’s), Thompson’s test (Thompson’s), Mishra’s first test (Mishra-I), and Mishra’s second test (Mishra-II) (Gangata, 2009; Machhindra et al., 2015; Mahajan, 2005; Mishra, 2001; Oudit et al., 2005; Pushpakumar et al., 2004; Schaeffer, 1909; Thompson et al., 1921). Several studies have assessed the utility of these examination manoeuvres (Kigera and Mukwaya, 2012; Kose et al., 2009; Kyung et al., 2012; Nasiri et al., 2016, Ndou et al., 2010; Machhindra et al., 2015; Sadeghifar et al., 2018; Sebastin and Lim, 2006), but none of these studies compared their clinical tests against a reference standard, such as intraoperative findings or advanced imaging, to verify the presence or absence of the PL tendon.…”

A case of potentially lethal vascular variation in association with palmaris profundus muscle

“…Thorough knowledge about these variations is necessary to avoid iatrogenic injuries during carpal tunnel release or any other upper limb surgery. The absence of palmaris longus can be detected by a simple clinical test [13], that helps the surgeon to look for underlying vascular anomalies, but to detect the presence of palmaris profundus requires a thorough knowledge about possible muscular variations and radiological imaging like ultrasound and MRI.…”