Interventions for treating ulnar collateral ligament injuries of the thumb

  • Protocol
  • Intervention



This is the protocol for a review and there is no abstract. The objectives are as follows:

To assess the effects (benefits and harms) of interventions (conservative or surgical) for treating ulnar collateral ligament injuries of the thumb.


Description of the condition

Ligaments are strong bands of tissue that link bones together at a joint. The ulnar collateral ligament (UCL) of the thumb is attached to the first metacarpophalangeal (MCP) joint, which is at the base of the thumb. The UCL is located on the medial (inner) side of the MCP joint, extending from the head of first metacarpal (the bone between the wrist and the thumb) and the base of the proximal phalanx (the base of the thumb). The function of the UCL is to prevent hyperabduction (extreme outward deviation) and forward displacement of the MCP joint of the thumb (Richard 1996).

UCL injuries can result from acute trauma, such as a fall on an outstretched hand or grasping an object during a fall. For example, if a skier falls with a pole in their hand during skiing, the handle of the pole may act as a fulcrum, applying force across the MCP joint and thereby putting the UCL under stress. Nowadays, UCL tears are often called 'skier's thumb' due to the high prevalence of UCL injury in skiers (Gerber 1981). UCL tears may also result from repetitive stress over a period of time as noted by Campbell who coined the term 'gamekeeper's thumb' (Campbell 1955). He noted that the gamekeeper's method of killing small animals such as rabbits put a particular stress on the MCP joint that, over time, injured the UCL. In clinical practice, repetitive injuries to the UCL are infrequently encountered as compared with acute injuries (Ritting 2010). In addition to repetitive stress or progressive incompetency, the term 'chronic injury' includes cases where initial diagnosis was missed and treatment delayed. UCL tears can be partial or complete and may involve an avulsion fracture, where a bone fragment is pulled away from the main bone. The UCL is usually torn at or near its insertion on the proximal phalanx (distal end).

As a result of these injuries, there is pain, swelling, bruising and difficulty in moving the thumb. Instability of the joint and weakness of pinch grip (between thumb and index finger) also occur. The weakness of pinch grip leads to marked limitation of basic activities of daily living such as opening jars or turning keys. If left untreated, the joint laxity (instability) may lead to degeneration (arthrosis/arthritis) of the thumb MCP joint. In some cases of complete UCL rupture, a painful nodular swelling results from the retraction of the torn part of the ruptured UCL, which becomes trapped under the adductor aponeurosis (a hand muscle that helps move the thumb). The adductor aponeurosis prevents the ruptured ends from making contact and thus healing of UCL on its own becomes impossible. This common type of complete rupture is known as a Stener lesion (Stener 1962).

The incidence of UCL injury has been reported to be between 2.2 to 4.4 per 1000 skiing days (Derkash 1987). A cohort study of the injury profile of alpine skiers found increased risk of thumb injury in males (Westin 2012). One study found that UCL injury accounted for approximately 86% of all the injuries of the thumb MCP (Moutet 1989). This injury has also been noted in other sports such as rugby, soccer, handball, basketball, volleyball, wrestling, martial arts and even after a handshake (Dey 2003; Moutet 1989; Rettig 2004). It has been suggested that people with less range of motion in the MCP joint (which in turn depends on the shape of the metacarpal head) are more susceptible to UCL injury (Richard 1996).

Diagnosis of UCL injury is based on patient history, clinical examination and other investigations. Other investigations include clinical stress testing under local anaesthesia, X-rays (routine or stress views), ultrasound, magnetic resonance imaging and arthrography. These injuries are frequently missed by inexperienced medical personnel (Musharafieh 1997).

Description of the intervention

UCL injuries can be treated surgically or non-surgically. Non-surgical or conservative options include plaster or splint immobilization (Sollerman 1991). Typically, the MCP joint is immobilized in the position of mild flexion and slight ulnar (inward) deviation at the MCP joint for four to six weeks. This positioning brings the torn ligament fragments closer, thus facilitating healing. A variety of plaster casts and splints are described in the literature. The standard thumb spica cast consists of layers of plaster of Paris or fibreglass molded over and enclosing the thumb, wrist and forearm. Other casts described in the literature include a modified thumb spica cast allowing removal and wrist motion (Primiano 1986), and a glove spica cast reported as enabling immediate return to activities or sports (Campbell 1992).

Unlike casts, splints are non-circumferential (and thus do not encircle the thumb or wrist) immobilizers that can accommodate swelling. The thumb spica splint consists of either a fabric enclosing a moderately pliable metal piece along the part that supports the thumb, or fiberglass/thermoplastic that can be cut and molded accordingly. Prefabricated and over-the-counter splints are also available. The splints may have adjustable straps to make them fit snugly around the thumb as well as the forearm. Immobilization is followed by physiotherapy, which includes joint mobilization followed by strengthening exercises.

Surgical options are 'direct repair', 'reconstruction' and 'arthrodesis' (joint fusion). Direct repair involves suturing the torn ligament ends together and/or fixing avulsed bone fragments such as with a pin or screw (Chuter 2009). Arthroscopic repair has been described as an alternative to open repair (Ryu 1995). One type of 'repair' of chronic UCL tears is the technique of condylar shaving (medial aspect of phalanx and metacarpal) (Haddock 2009).

Reconstruction often involves replacement with a graft, usually obtained from another part of the patient's hand (autograft), or using other nearby structures to stabilise the thumb (Fairhurst 2002). It is usually done for chronic lesions, where the ligament ends may not be in a good enough state for repair. It entails replacing the remnants of the torn UCL with a graft. Reconstruction may be a static (using a free tendon graft that has been extracted from elsewhere) or a dynamic tendon transfer (a tendon end, typically of the adductor pollicis, is relocated). The hand tendons commonly used as sources of grafts include the palmaris longus, flexor carpi radialis, flexor carpi ulnaris and the extensor pollicis brevis. A bone-soft tissue-bone graft has also been used to reconstruct UCLs (Wong 2009).The tendon grafts can be fixed by passing them through bone tunnels and securing them with a staple, button or screw; or by securing the graft to the bone surface using suture anchors (without needing to create bone tunnels). Some reconstructions may include suturing the MCP joint capsule (capsulorrhaphy) or, as mentioned above, advancement of the insertion of adductor pollicis.

Arthrodesis (joint fusion) involves removing the articular cartilage of both bones at the MCP joint and fixing the bone ends together with transarticular K-wires or screws or plates. This effectively removes the joint to form one length of bone. It is generally considered a salvage procedure, reserved for more severe injuries such as articular damage and cases of failed ligament repair or reconstruction (Baskies 2009; Fairhurst 2002).

After surgery, the MCP joint is placed in a cast or splint for four to six weeks. This is followed by physiotherapy, which includes joint mobilization followed by strengthening exercises.

How the intervention might work

The choice of treatment is influenced by a number of factors such as time of presentation (acute or chronic), associated bony avulsion (displaced or non-displaced), presence of Stener lesion, the site of ligament tear (the end or mid-substance) and the degree of thumb instability.

Conservative treatment is usually adopted in cases of acute injury where the ligament ends are in close proximity, such as in a partial tear. Cast or splint immobilization of the thumb MCP joint for a period of four to six weeks allows time for the torn ligament to rest and heal in an optimal position, and removes stresses resulting from movement during daily activities. Although this should facilitate healing of the UCL, while preventing further damage, casts are cumbersome, interfere with daily activities and usually have to be removed by attending a clinic. Additionally, the immobilized joint(s) can become stiff, which results in an increased need for physiotherapy after cast removal. By not enclosing the joint, splints and some types of cast allow for adjustments to accommodate hand swelling. Typically, splints are also lighter in weight and can be removed for daily activities of living such as bathing and skin care. Conversely, splints provide less protection than casts from pulls and jerks on the UCL during daily activities. Advocates of functional splinting argue, however, that controlled early active motion stimulates healing of ligaments (Michaud 2010). Similar considerations apply to cast or splint immobilization applied after surgery.

Surgery is necessary for restoring the UCL and joint function for UCL injuries such as Stener lesions, where the ruptured ends of the UCL need to be brought together again. The disadvantages of surgery include infection, iatrogenic injury, implant failure, neurovascular complications and joint stiffness. Compared with open repair, arthroscopic repair of the UCL is more technically demanding as the MCP joint is small and there is risk of damage to the articular cartilage from the instrumentation.

Reconstruction is a complex operation usually done for chronic lesions, where the ligament has degenerated over time and a direct repair may not hold or has not held. The disadvantages of reconstruction include the derangement of local functioning tissues (grafts) and complexity of procedures. Although reconstruction is usually reserved for chronic tears or failed primary repair, some authors have recommended repair over reconstruction even for chronic UCL tears (Ahmed 2012; Haddock 2009; Pai 2008).

Arthrodesis (joint fusion) is a salvage operation reserved for failed surgery or in the presence of joint pathology such as arthritis, which would otherwise make repair or reconstruction of the UCL futile. Arthrodesis achieves a pain-free, stable joint at the cost of lost mobility.

Why it is important to do this review

In one study, UCL injury accounted for approximately 86% of all the injuries of thumb MCP (Moutet 1989). It is an injury that is frequently missed by inexperienced healthcare personnel in the emergency department (Gerber 1981) and can be quite disabling for the patient if it is inadequately or improperly treated. There is also no consensus on the line of management, whether conservative or surgical, to be followed for either acute or chronic injury. With conservative management, there is uncertainty as to the best type of immobilization (plaster or splint) and optimum duration of immobilization. For acute UCL tears, some clinicians favor surgical management (Glickel 2005; Tsiouri 2009), especially if the tear is associated with high instability (as seen in a complete tear) (Derkash 1987; Posner 2012; Richard 1996; Weiland 1997). However, other clinicians favor conservative management (Abrahamsson 1990; Coonrad 1968; Landsman 1995; Pichora 1989).

In surgical management, reconstruction is usually reserved for chronic tears, but some prefer primary repair (Ahmed 2012; Pai 2008). There are different techniques of primary repair and reconstruction with uncertainty about which is the optimum technique for both methods. The optimal graft material for reconstruction of UCL is also unclear.

Our literature search revealed only a single systematic review on this topic (Samora 2013), with a search date of November 2011. Samora 2013 included a mixture of study designs including retrospective comparisons and case series, but excluded non-English language studies and studies with follow-up periods of less than two years. Our systematic review aims to clarify the best line of management for UCL injury based on the best available evidence from randomized controlled trials. This review will also help identify key areas where further research is required.


To assess the effects (benefits and harms) of interventions (conservative or surgical) for treating ulnar collateral ligament injuries of the thumb.


Criteria for considering studies for this review

Types of studies

Randomized controlled trials and quasi-randomized (method of allocating participants to a treatment that is not strictly random, e.g. by hospital number) controlled trials evaluating acute or chronic ulnar collateral ligament (UCL) injuries of the thumb.

Types of participants

People of any age with acute or chronic injury (due to either repetitive stress or treatment delay) of the UCL of the thumb with or without an associated avulsion fracture of phalanx. We will set a provisional threshold of three weeks to distinguish between acute and chronic UCL injury, but this may also depend on the definitions used in the included trials.

Types of interventions

The types of UCL injury to which the following comparisons apply are expected to differ between comparisons. For instance, it is unlikely that Stener lesions would be treated conservatively or, conversely, that partial tears would be treated surgically.

  1. Different methods of non-surgical (conservative) management. The main comparisons will be:

    1. functional splint versus plaster cast

    2. newer casting methods (e.g. fiberglass casts) versus plaster of Paris casts

    3. shorter periods of immobilization (three to four weeks) versus longer periods of immobilization (six weeks or more)

  2. Surgical versus conservative treatment

  3. Different methods of surgical intervention. The main comparisons will be:

    1. reconstruction versus repair

    2. arthroscopic repair versus open repair

    3. static grafts versus dynamic grafts for reconstruction

  4. Different methods of post-surgical immobilization. The same comparisons as listed for conservative management will apply.

Types of outcome measures

Primary outcomes
  1. Thumb function as evaluated by tools such as the Michigan Hand Outcomes Questionnaire (MHQ) (MHQ 1998) and Disabilities of the Arm, Shoulder and Hand (DASH) scores (DASH)

  2. Adverse effects: persistent stiffness, persistent swelling, skin irritation, pressure sore, infection, delayed wound healing, neurovascular complications, failure of conservative treatment, re-operation, graft and implant-related complications

Secondary outcomes
  1. Quality of life as measured by validated scale, e.g. WHO Quality of Life-BREF (WHOQOL-BREF 1991)

  2. Pain (visual analogue scale)

  3. Hand grip and key pinch strength

  4. Resource use (e.g. duration of hospitalisation) and other costs

Timing of outcome measurement

Where possible, we plan to group outcome data as short-term follow-up (up to 3 months after random allocation); medium-term follow-up (between 3 and 12 months) and long-term follow-up (1 year or more).

Search methods for identification of studies

Electronic searches

We will search the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to present), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library current issue), MEDLINE (1946 to present), EMBASE (1980 to present) and SPORTDiscus (1985 to present). We will also search the WHO International Clinical Trials Registry Platform and for ongoing and recently completed studies. We will apply no restrictions based on language or publication status.

In MEDLINE, a subject-specific strategy will be combined with the sensitivity-maximizing version of the Cochrane Highly Sensitive Search Strategy for identifying randomized trials (Lefebvre 2011) (see Appendix 1). This strategy will be modified for use in the other databases.

Searching other resources

We will search reference lists of selected articles and abstracts from relevant conference proceedings to identify other trials.

Data collection and analysis

Selection of studies

Two authors (SSM, DRP) will independently screen the results of the search for potentially eligible studies, for which we will attempt to retrieve full text articles. The same two authors will then independently perform study selection based on the trial reports of all potentially eligible studies using a study eligibility form that lists the inclusion criteria and prompts for reasons for exclusion of studies. Any issue or concerns over screening or study selection will be dealt with by discussion or with the help of another author if needed. We will not take any measures to mask the trial authors, institutions and trial results during our assessments.

Data extraction and management

Three authors (SSM, RRD, DRP) will independently extract data for primary and secondary outcomes using a data collection form. If there is any difference of opinion, consensus will be reached by discussion among all the authors. Following data extraction, one author (SSM) will enter the data into Review Manager 5 software (RevMan 2014) and another author (RRD) will cross check for any errors or disparities.

We will collect, among other items, the following:

  1. method and setting - year of the study, study duration, type of randomization, allocation concealment method, blinding, study location and sampling method;

  2. participants - number of participants in the intervention groups, age, sex, timing of injury and other baseline characteristics, and loss to follow-up with reasons;

  3. interventions - full details of interventions being compared, timing of interventions, details of care programmes;

  4. outcomes - primary and secondary outcomes as mentioned above, any other outcomes assessed, times of assessment and length of follow-up, and results;

  5. notes - published or unpublished data, title, authors, source, contact address, language of publication, year of publication and funding sources, if any.

We will resolve any issues and concerns in data extraction by discussion and consensus.

Assessment of risk of bias in included studies

Two authors (SSM, HHKS) will independently assess the risk of bias of the included studies by using the criteria outlined in Chapter 8 of the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011a).

We will assess the following six domains for each trial:

  1. random sequence generation (selection bias);

  2. allocation concealment (selection bias);

  3. blinding of participants and personnel (performance bias);

  4. blinding of outcome assessment (detection bias);

  5. incomplete outcome data (attrition bias) through withdrawals, dropouts and protocol deviations;

  6. selective reporting bias.

We will also assess for any other sources of bias such as bias related to the specific study design, inappropriately early or abrupt end of trials or potential conflicts of interest.

For each of the mentioned categories, we will assign one of the following risks of bias judgments: ‘low risk’, ‘high risk’, or ‘unclear risk’ of bias.

We will resolve any concerns or issues by discussion or with help from another author (RRD).

Measures of treatment effect

For data analysis, we will follow the guidelines set out in Chapter 9 of theCochrane Handbook for Systematic Review of Interventions (Deeks 2011).

For dichotomous data, we will present results as risk ratios (RR) together with 95% confidence intervals (CI). For continuous data, we will present mean differences (MD) and 95% CIs. However, if different scales are used to measure the same outcome, we will use the standardized mean difference (SMD) with 95% CIs.

Unit of analysis issues

We anticipate that the unit of randomization and analysis in the included trials will be the individual patient. However, trials including people with bilateral injuries (both thumbs have these injuries) may present results for thumbs rather than individual patients. Where such a unit of analysis issue arises and appropriate corrections have not been made, we will consider presenting the data for such trials only where the disparity between the units of analysis and randomization is small. Where the data are pooled, we will perform a sensitivity analysis to examine the effect of excluding incorrectly reported trials from the analysis. We will be aware of other potential unit of analysis issues, including multiple observations of the same outcome (such as when a patient experiences multiple complications or has received multiple modes of treatment) or multiple time points. For the latter, we will use data from clinically relevant time points and analyze these separately.

Dealing with missing data

For any missing data or unclear information, we will try to contact the primary investigator. Although we recognize that intention-to-treat analysis in randomized clinical trials is the methodology of choice, in studies where data are missing due to participant dropout, we will conduct a primary analysis based on participants with complete data. It will be assumed that missing outcomes will not be a problem if loss to follow-up is well documented and unrelated to outcomes in both study arms, as advised in chapter 16 of theCochrane Handbook for Systematic Review of Interventions (Higgins 2011b). However, if the reasons for missing data are not available, we will examine the possible effects of the missing participants/data through sensitivity analysis; for example, using a worst and best case analysis or testing the effects of excluding trials with missing data from a meta-analysis.

Assessment of heterogeneity

We will use the Chi2 test for assessing heterogeneity (significance level P < 0.1). Quantification of the degree of heterogeneity will be done by using the I2 statistic (Deeks 2011). The guidelines for interpretation of the I2 values will be as follows: 0% to 40% indicates unimportant levels of heterogeneity; 30% to 60% indicates moderate heterogeneity; 50% to 90% indicates substantial heterogeneity; 75% to 100% indicates very substantial heterogeneity.

Assessment of reporting biases

We will assess publication and reporting bias by using a funnel plot if we have 10 or more studies. We will visually examine the funnel plot for symmetry, with greater symmetry potentially indicating a lower risk of reporting bias.

Data synthesis

When considered appropriate, results of comparable groups of trials will be pooled using both fixed-effect and random-effects models. The choice of the model to report will be guided by a careful consideration of the extent of heterogeneity and whether it can be explained, in addition to other factors such as the number and size of studies that are included. Ninety-five per cent confidence intervals will be used throughout. We will consider not pooling data where there is considerable heterogeneity (I² > 75%) that cannot be explained by the diversity of methodological or clinical features among the trials. Where it is inappropriate to pool data, we will still present trial data in the analyses or tables for illustrative purposes and report these in the text.

Subgroup analysis and investigation of heterogeneity

If we find heterogeneity (more than 50%), we will attempt to explore it by conducting subgroup analysis or meta-regression (if more than 10 studies are included in a meta-analysis).

While we may not conduct formal subgroup analysis, we will present the following subgroups where possible:

  • acute versus chronic injury;

  • partial versus complete tear;

  • isolated UCL tear versus UCL tear associated with proximal phalanx avulsion fracture;

  • initial (definitive) treatment for comparisons of cast/splint immobilization (conservative versus repair versus reconstruction).

We will investigate whether the results of subgroups are significantly different by inspecting the overlap of the CIs and performing the test for subgroup differences available in Review Manager software (RevMan 2014).

Sensitivity analysis

We will carry out sensitivity analysis to investigate the robustness of the results regarding the various components of risk of bias. We will examine the effect on the primary outcome of excluding any study judged to be at high risk of bias in three of the domains: sequence generation; allocation concealment; blinding of outcome assessment. We will also explore other aspects of trial and review methodology such as the selection of statistical model (fixed-effect versus random-effects) for meta-analysis, and the inclusion of trials only reported in conference abstracts, with missing data or with unit of analysis issues relating to the inclusion of participants with bilateral injuries.

Assessment of quality of the evidence

We shall use the GRADE approach to assess the quality of evidence (high, moderate, low or very low) for all outcomes listed in Types of outcome measures (Chapter 12.2,  Higgins 2011a). Where there is sufficient evidence, we will prepare 'Summary of findings' tables.


We thank Laura MacDonald and Diane Horsley for their help and for managing the editorial process for the protocol. We also thank Joanne Elliott for developing the search strategy. We thank Catherine Sherrington and Helen Handoll (editors) and David Warwick (external referee) for their helpful feedback.


Appendix 1. Search Strategies

MEDLINE (Ovid Online)

1 Thumb/
3 1 or 2
4 (ulna* collateral ligament or UCL).tw.
5 (metacarpophalangeal joint or MCP).tw.
6 Metacarpophalangeal Joint/
7 Collateral Ligaments/
8 4 or 5 or 6 or 7
9 3 and 8
10 ((gamekeeper* or skier*) adj thumb).tw.
11 9 or 10
12 (injur* or strain or tear* or torn or ruptur* or repair* or reconstruct*).tw.
13 Injuries.fs.
14 12 or 13
15 11 and 14
16 Randomized Controlled
17 Controlled Clinical
18 randomized.ab
19 placebo.ab.
20 Drug Therapy.fs.
21 randomly.ab.
22 trial.ab.
23 groups.ab.
24 or/16-23
25 exp Animals/ not Humans/
26 24 not 25
27 15 and 26

/: Medical Subject Heading (MeSH)
tw: text word (title, abstract, keywords)
*: truncation

adj: proximity operator
pt: publication type
ab: abstract
fs: floating subheading

Contributions of authors

SSM, DRP, RRD, HHKS: literature search for background, writing the background, objectives and inclusion criteria sections, outcome measures and methods.

Declarations of interest

Simerjit S Madan: none known
Dinker R Pai: none known
Ruchita Dixit: none known
Htoo Htoo Kyaw Soe: none known